Starmer announces plan to ban teen social‑media use

May 31 rises to 23%4%

Starmer’s proposal to consider an Australia‑style ban on teenage social‑media access was viewed as a bold policy move, nudging the May‑31 price up from 19% to 23% as the market saw a potential distraction from leadership pressures.

Starmer apologizes for Mandelson appointment amid mounting pressure

December 31 rises to 73%4%

Starmer publicly apologized for appointing Mandelson as ambassador despite his Epstein ties, acknowledging the damage to trust and increasing calls for his resignation, which influenced market prices for later outcomes.

Starmer meets Xi Jinping, calls for deeper UK-China ties amid global turbulence

December 31 rises to 70%2%

Starmer's diplomatic efforts to strengthen UK-China relations aimed to boost economic prospects and stabilize his leadership image, contributing to a rise in the December 31 market outcome despite domestic challenges.

Labour blocks Manchester Mayor Andy Burnham's bid for Parliament seat

Labour's National Executive Committee, including Starmer, blocked Burnham's candidacy, seen as a potential leadership challenger, reflecting internal party tensions and affecting market confidence in Starmer's stability, impacting May 19 and May 31 outcomes.

Starmer’s chief of staff resigns over Mandelson-Epstein scandal

December 31 surges to 87%27%

Morgan McSweeney, Starmer’s chief of staff, resigned taking responsibility for advising the controversial appointment of Mandelson, intensifying pressure on Starmer and contributing to a sharp rise in market prices for Starmer leaving by December 31.

Labour blocks Andy Burnham’s bid for Parliament seat, sparking party row

June 30 rises to 41%3%

The decision to block popular Manchester Mayor Andy Burnham from standing in a parliamentary by-election fueled internal Labour Party tensions and speculation about leadership challenges to Starmer, influencing market uncertainty around his tenure.

Labour blocks Andy Burnham's bid for Parliament, sparking internal party row

May 19 drops to 6%8%

The decision to block a popular rival's parliamentary bid fueled speculation of internal party conflict and leadership challenges to Starmer, reflecting growing instability within Labour ahead of local elections.

Labour suffers heavy losses in local elections, Reform UK gains ground

May 15 plunges to 0%25%

The poor performance of Labour in the May 7 local elections, with significant gains by Reform UK, led to a sharp drop in market confidence for Starmer's short-term survival, especially for May 15 and May 19 outcomes.

Starmer meets with Japanese leaders on cybersecurity and critical minerals

During a stop in Tokyo, Starmer secured a cooperation deal with Japan on cybersecurity and critical minerals, signalling a proactive foreign‑policy agenda that briefly lifted confidence in his tenure.

Starmer announces UK‑Norway joint naval patrols to protect undersea cables

The AP story on joint UK‑Norway naval operations was viewed as a strong security move, lifting the December‑31 contract again after a brief dip in April.

UK and Norway sign joint naval patrol agreement

December 31 rises to 69%1%

The defense pact was portrayed as a strong foreign‑policy win for Starmer, briefly lifting the December‑31 price from 68% to 69% as market sentiment improved.

UK and Norway launch joint naval patrols to protect undersea cables

December 31 jumps to 68%7%

The defence cooperation was interpreted as a strong security move by Starmer, nudging the December‑31 outcome upward as confidence in his leadership rose.

Starmer meets Xi Jinping to deepen UK-China ties amid global turbulence

December 31 surges to 67%15%

Starmer’s visit to China and meeting with President Xi Jinping aimed to improve diplomatic and economic relations, signaling a strategic partnership. While positive for Starmer’s international standing, it had limited impact on his domestic leadership market.

Starmer meets Xi Jinping in Beijing, pledges deeper UK‑China partnership

June 30 rises to 45%3%

The high‑profile diplomatic trip was seen as a boost to Starmer’s economic agenda, lifting the June‑30 and December‑31 outcomes as investors perceived reduced political risk.

Starmer meets Xi Jinping in Beijing, pledges deeper UK‑China partnership

The same visit also raised the May‑19 outcome modestly as the market viewed the foreign‑policy success as a sign of Starmer’s continued authority.

Starmer proposes teen social‑media ban, sparking public debate

Starmer announced that a ban on social‑media use for under‑16s was being considered, echoing Australia’s policy. The proposal was controversial and seen as a distraction from governance, causing a dip in the December‑31 price.

Starmer defends UK stance on Arctic security amid US‑China tensions

AP covered Starmer’s comments on Arctic security, reinforcing his image as a steady leader and contributing to a modest rise in the December‑31 contract.

Peter Mandelson arrested on suspicion of misconduct in public office

December 31 surges to 73%22%

Following the release of Epstein-related documents, British police arrested Mandelson, intensifying the scandal and increasing pressure on Starmer, which caused a sharp rise in the December 31 market price.

Starmer vows not to quit after local elections deliver losses for Labour

May 31 jumps to 31%12%

Following poor local and regional election results in May 2026, Starmer insisted he would not resign despite significant losses for Labour and gains for Reform UK. This tempered market expectations for an immediate departure, causing some price volatility especially for the May 31 and May 19 outcomes.

Labour faces special election loss in Greater Manchester, raising leadership concerns

June 30 drops to 43%7%

The anticipated loss in a Greater Manchester special election intensified speculation about Starmer's leadership future, contributing to a decline in market confidence for his continuation through mid-2026.

Peter Mandelson arrested amid Epstein scandal, intensifying pressure on Starmer

December 31 surges to 73%21%

The arrest of Mandelson, Starmer's appointee and Epstein associate, escalated the political crisis, severely undermining Starmer's judgment and increasing calls for his resignation, causing market volatility.

Starmer apologises for Mandelson appointment, vows transparency

Starmer publicly apologized for appointing Mandelson and promised to release related documents, attempting to calm party unrest. The apology was enough to halt the price surge, causing a modest pull‑back.

Starmer faces parliamentary pressure after police open Mandelson investigation

Metropolitan Police launched a criminal investigation into former ambassador Peter Mandelson over alleged leaks to Jeffrey Epstein. The development revived questions about Starmer’s judgment and raised the risk of a leadership challenge, pushing the December‑31 price sharply upward.

Starmer releases documents on Mandelson’s vetting process

December 31 drops to 62%8%

Starmer’s promise to publish vetting files was seen as an attempt to contain the scandal, but the partial release further eroded confidence, contributing to a dip from 70% to 62% on February 13.

Starmer secures UK‑US trade deal reducing tariffs on key industries

AP reported a trade agreement with the United States that was seen as a major economic win for Starmer, driving the December‑31 contract to a new high in early February.

UK police launch criminal investigation into Peter Mandelson over Epstein leaks

December 31 jumps to 70%8%

The launch of a formal police probe heightened pressure on Starmer, coinciding with a jump in the December‑31 price from 62% to 70% as traders priced in a possible leadership crisis.

Starmer’s chief of staff resigns amid Mandelson‑Epstein revelations

May 31 jumps to 26%7%

The same resignation also caused a dramatic swing in the May‑31 outcome as traders priced in a higher risk of an imminent resignation.

Starmer’s chief of staff resigns amid Mandelson‑Epstein revelations

June 30 surges to 48%26%

Morgan McSweeney quit, citing responsibility for the Mandelson appointment; the resignation intensified scrutiny of Starmer’s judgment and drove the June‑30 and May‑31 outcomes sharply upward.

Starmer faces leadership crisis over Mandelson Epstein appointment scandal

June 30 surges to 57%29%

Revelations that Peter Mandelson was appointed ambassador to the US despite failing security checks and his ties to Jeffrey Epstein triggered a political crisis for Starmer, with calls for his resignation and cabinet ministers rallying around him. This event caused a sharp increase in the market's probability for Starmer leaving by June 30 and December 31.

Starmer announces new UK‑Japan cybersecurity and critical minerals pact

The AP article on the UK‑Japan agreement highlighted Starmer’s active foreign policy, which helped push the December‑31 contract back up toward its peak.

UK police open criminal investigation into Peter Mandelson

December 31 jumps to 73%11%

The Metropolitan Police launched a criminal investigation into Peter Mandelson for potential misconduct in public office related to his relationship with Jeffrey Epstein, significantly increasing pressure on Starmer.

Starmer faces parliamentary backlash over Mandelson ambassador appointment

December 31 rises to 61%4%

After the Guardian revealed that Peter Mandelson failed security vetting, Starmer’s handling of the appointment sparked calls for his resignation, pushing the December‑31 option up from 57% to 61%.

Starmer’s government announces strategic partnership with China

Starmer’s visit to Beijing and the signing of a strategic partnership were framed as a boost to the UK economy. Traders viewed the diplomatic win as a sign of political stability, nudging the December‑31 probability higher.

Starmer meets with European leaders amid ongoing political pressure

December 31 rises to 60%3%

Starmer's engagement with European leaders highlighted his efforts to maintain international standing despite domestic turmoil, but did not significantly improve market confidence in his near-term tenure.

Starmer meets US President Trump to discuss NATO and Greenland

AP reported a high‑profile meeting between Starmer and Trump, which temporarily raised concerns about UK‑US relations and caused a short‑term dip in the December‑31 contract.

Starmer's chief of staff resigns over Mandelson-Epstein scandal

December 31 rises to 56%4%

Morgan McSweeney resigned as Starmer's chief of staff, taking responsibility for advising the Prime Minister to appoint Peter Mandelson, further intensifying the political crisis.

Starmer meets Xi Jinping to seek thaw in UK-China relations

December 31 rises to 57%4%

Starmer's visit to China aimed to boost the UK economy and improve diplomatic ties, but also highlighted tensions with the US and internal party concerns, impacting perceptions of his leadership stability.

Starmer faces parliamentary showdown after Mandelson appointment scandal erupts

December 31 jumps to 57%7%

Senior ministers rallied behind Starmer as MPs demanded answers over the appointment of Peter Mandelson as U.S. ambassador despite failed security vetting, raising doubts about Starmer’s leadership and pushing the December‑31 outcome higher.

Starmer's chief of staff resigns over Mandelson-Epstein ambassador appointment

December 31 jumps to 61%8%

Morgan McSweeney resigned taking responsibility for advising Starmer to appoint Mandelson as ambassador despite Epstein ties, escalating the political storm and further undermining Starmer's leadership, impacting the December 31 market outcome.

Starmer apologises for Mandelson‑Epstein revelations, promises investigation

Starmer’s public apology and the launch of a police investigation into Mandelson were covered by AP, causing a brief dip in the December‑31 contract before it recovered later in the window.

Labour lawmakers call for new leadership following Mandelson scandal

June 30 rises to 38%4%

Following the poor election results and ongoing controversy over the Mandelson appointment, several Labour lawmakers publicly questioned Starmer's leadership and called for a change.

Labour Party suffers major losses in local and regional elections

December 31 drops to 44%6%

The governing Labour Party experienced significant losses in local and regional elections, which were widely viewed as a referendum on Starmer's leadership and his handling of the Mandelson scandal.

Allies rally behind Starmer amid Mandelson‑Epstein controversy

Senior cabinet ministers publicly defended Starmer after the revelation that Peter Mandelson, a friend of Jeffrey Epstein, had been appointed ambassador to the United States despite failing security vetting. The show of party unity temporarily halted the market’s slide.

UK sanctions Russian GRU officers over cyber‑espionage attack

The AP detailed a new sanctions package targeting Russian intelligence officers, which was interpreted as a strong security stance by Starmer and nudged the December‑31 contract upward.

Starmer defends his record after local election losses

June 30 rises to 46%4%

Following a poor showing in local elections, Starmer publicly refused to resign, stabilising the market and nudging the price back up to 46 % as investors reassessed the likelihood of a leadership challenge.

Starmer begins diplomatic tour of China to boost trade

June 30 rises to 42%3%

Starmer travelled to Beijing for a strategic partnership meeting with President Xi, a move aimed at revitalising the economy. The visit was welcomed by markets, contributing to a modest price rise from 39 % to 42 % over the next few days.

Local and regional elections show heavy losses for Labour

Results released showing Labour losing more than half the seats it defended signaled deep voter dissatisfaction, increasing speculation of a leadership challenge and pushing the market higher for a resignation before the end of 2025.

Starmer’s chief of staff resigns over Mandelson‑Epstein fallout

June 30 drops to 26%9%

The chief of staff quit amid the growing controversy over Mandelson’s ties to Epstein, signaling internal turmoil and further eroding confidence in Starmer’s judgment, which coincided with the market’s trough at 26 %.

Allies rally behind Starmer as Mandelson‑Epstein scandal erupts

June 30 plunges to 35%16%

AP reported that senior cabinet ministers publicly defended Starmer after revelations that Peter Mandelson, a friend of Jeffrey Epstein, had been appointed ambassador despite failing security vetting. The scandal intensified pressure on Starmer’s leadership, prompting a sharp drop in the market’s Yes probability.

Starmer leads UK delegation to China for strategic partnership talks

AP reported Starmer’s four‑day visit to Beijing, aimed at deepening UK‑China ties, which helped lift longer‑dated contracts as the market saw diplomatic engagement as a sign of political stability.

Labour suffers heavy losses in UK local and regional elections

The local elections delivered a decisive defeat for Starmer’s Labour Party, with the party losing more than half the seats it defended. The result was interpreted as a de‑facto referendum on Starmer’s leadership, prompting a sharp rise in the probability he would step down before year‑end.

Revelations of Mandelson's failed security vetting and Epstein ties rock Starmer's leadership

December 31 plunges to 35%15%

The disclosure that Peter Mandelson was appointed ambassador to the US despite failing security checks and his friendship with Jeffrey Epstein triggered a major political crisis for Starmer, leading to calls for his resignation and a drop in market confidence for near-term departure.

Starmer faces backlash after Labour suffers losses in local elections

December 31 dips to 50%1%

Labour's poor performance in local elections led to calls within the party for Starmer to resign, reflecting declining confidence in his leadership amid economic and policy challenges. This event increased market speculation about Starmer's potential departure by year-end.