French President Emmanuel Macron is set to outline his vision for how France's nuclear arsenal could bolster European defense, amidst growing concerns about Russia's aggression and shifting US priorities.

• France, the EU's only nuclear power, maintains the world's fourth-largest nuclear arsenal, estimated at around 290 warheads.
• Key figures involved include President Macron, German Chancellor Friedrich Merz, and UK Prime Minister Keir Starmer, with discussions centering on potential nuclear cooperation.
• Macron's speech at the Ile Longue nuclear submarine base is expected to introduce "fairly significant shifts and developments" in France's nuclear doctrine.