US SB2914

Designates nine NATO countries bordering Russia, Belarus, or Ukraine (Bulgaria, Estonia, Finland, Hungary, Latvia, Lithuania, Poland, Romania, and Slovakia) as "Eastern Flank strategic defense partners" eligible for priority security assistance

Requires partner countries to commit to allocating 5% of GDP to defense by 2035, with at least 3.5% for core defense requirements and NATO capability targets

Directs the Secretary of State and Secretary of Defense to prioritize these partners for Foreign Military Financing, capacity-building assistance under Section 333, excess defense article transfers, and military exercises

Mandates the Secretary of Defense to prioritize Eastern Flank partners under the War Reserve Stocks for Allies program and consider expanding pre-positioned stockpiles in partner countries

Requires a congressional briefing within 180 days of enactment on implementation timelines, goals, and cooperative mechanisms