"Thank you to the Ukrainian people for their bravery. We are here and we will not weaken," Macron said at Omaha Beach, as guests rose to acknowledge Zelensky and French jets roared above in a fly-past.

"Faced with the return of war on our continent... faced with those who purport to change borders by force to re-write history, let us be worthy of those who landed here," Macron said, referring to Russia's invasion of Ukraine in 2022 and the ensuing conflict.

"Your presence here today... speaks to all of this," Macron said to Zelensky at the ceremony marking the 80th anniversary of D-Day landings in northern France.

The commemorations provided a hugely symbolic backdrop to talks on how Kyiv can regain ground after Russian advances, with Zelensky attending the ceremony alongside Biden, Britain's King Charles III and Canadian Prime Minister Justin Trudeau.

No Russian official was invited, underlining Moscow's current pariah status despite the decisive Soviet contribution to defeating Nazism in World War II.

Russian leader Vladimir Putin has shrugged off the lack of an invitation for Russia, saying "let them celebrate without us".

But French hosts paid tribute to the Soviet Union's sacrifices at the ceremonies.

At the main D-Day event, Macron pointed to "the resolute commitment of the Red Army", saying millions of Soviets inflicted heavy losses on Nazi Germany "at the cost of their own blood".