The Mecca Joint Defence Agreement, signed in August 2026 by Saudi Arabia, Turkey, and Pakistan, established a mutual defense framework modeled on collective security principles, with an explicit openness to expansion. Trader sentiment reflects limited near-term accession prospects despite public expressions of interest from Egypt, which is reviewing legal and technical issues after Turkish statements positioning it as a likely next member; Bangladesh, which has signaled positive consideration; Syria, which is assessing options; and Iran, which received conflicting reports of an invitation. No formal accessions have occurred as of mid-October 2026, even after the pact's first activation in early October amid Houthi threats to Saudi infrastructure, which prompted institutional steps including a Riyadh secretariat and appointment of a Pakistani secretary-general. Potential barriers include existing alliances, constitutional hurdles, and the absence of finalized accession procedures, while scheduled diplomatic engagements and regional security consultations could influence timelines before any year-end resolution window.