PARIS (AFP) - French President Emmanuel Macron told Russian leader Vladimir Putin on Saturday (Feb 12) that "sincere dialogue" is incompatible with escalation as tensions mount over fears that Russia will invade Ukraine.

The two spoke for one hour 40 minutes, the French presidency said, amid a flurry of diplomacy aimed at dissuading Putin from marching on his western neighbour.

US President Joe Biden is due to speak to the Russian leader later on Saturday.

Macron and Putin "both expressed a desire to continue dialogue" on how to "advance the Minsk accords" on the restive Donbass region as well as "security conditions and stability in Europe", the presidency added.

Weeks of tensions that have seen Russia surround Ukraine with more than 100,000 troops intensified when the Kremlin launched its biggest naval drills in years across the Black Sea.

The exercises off the coast of Ukraine's Odessa added urgency to a hastily arranged call on Saturday between Biden and Putin aimed at defusing one of the gravest crises in East-West relations since the Cold War.