France, March 2 -- French President Emmanuel Macron is expected to rule out any form of shared European control over France's nuclear arsenal - while clarifying what Paris can offer allies who have doubts over the reliability of the United States' nuclear umbrella under President Donald Trump.

Speaking on Monday at France's Île Longue nuclear submarine base in Brittany, the French president is set to outline what aides have described as "fairly significant shifts and developments" in the country's nuclear doctrine.

For decades, Europe's security architecture has rested firmly on American guarantees. While France and Britain maintain independent nuclear arsenals, most European nations rely on Washington as the ultimate deterrent.

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