The Mecca Joint Defence Agreement, signed August 7, 2026, by Saudi Arabia, Turkey, and Pakistan, entered into force in early November after ratifications and establishes a mutual-defense framework modeled on collective security principles, with accession open only by unanimous consent of the core parties through a new Strategic Political and Defence Committee. Recent developments include ongoing bilateral consultations, Turkish statements highlighting Egypt as a prospective member once technical issues are resolved, and expressions of interest from Qatar, Bangladesh, Syria, and Iran, though no formal accessions have occurred. The roughly seven-week window to December 31 imposes tight procedural constraints, including committee approval, domestic legislative steps in candidate states, and alignment on defense commitments amid active regional tensions such as Houthi strikes on Saudi targets. Trader pricing reflects these institutional and timeline barriers, with Egypt and Qatar showing comparatively elevated but still limited implied probabilities.