BBC News

Édouard Philippe is the second French leader to travel there, after then-President François Mitterrand in 1993.

Mr Philippe laid flowers at memorials for the dead on both sides, and called for France and Vietnam’s “common past” to be remembered “in a peaceful way”.

The Dien Bien Phu battle raged for 56 days between March and May in 1954.

The outnumbered French troops, trapped in a remote valley north of Hanoi, were crushed by pro-independence Vietnamese fighters.

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The battle led to the 1954 Geneva peace accord, which divided Indochina – until then a French colony – between the communist north, and a pro-US regime in the south.

On Saturday, Mr Philippe visited France’s former underground command centre at Dien Bien Phu and lit incense at a memorial plaque.

“It is difficult to imagine that for several months this was the site of intense fighting rarely seen,” he said, adding that he wanted to convey a “message of admiration, respect and pride”.

France is a major trading partner for Vietnam, and Mr Philippe began his visit there by signing deals in the capital, Hanoi.

Asked about critics who have questioned his decision to visit the site of a crushing defeat for his country, he said: “What I find surprising is the fact so few people have done this before me.”