Macron was due to speak with Ukrainian President Volodymyr Zelensky Wednesday before traveling to Brussels for an emergency EU summit on Thursday to agree on sanctions if Moscow launches an all-out assault on its neighbor.

A virtual meeting of the G7 group of leading democracies is also scheduled for Thursday.

Russian President Vladimir Putin on Monday decided to recognize the independence of Ukraine's breakaway republics of Donetsk and Lugansk, sharply escalating the diplomatic stand-off and triggering international condemnation and sanctions.

Ukraine has received substantial military backing from NATO members, including anti-aircraft and anti-tank missiles and helmets, as the West accused Moscow of massing up to 150,000 troops on the border.

But Macron's advisers said diplomacy was the answer in the face of Russian firepower.

"Taking into account the power balance, deliveries of military equipment would not allow Ukraine to stand up to Russia," Macron's advisers said.

"The solution is through diplomacy" and trying to "deter" Russia, they added.

The statement from the French president's office Wednesday warned it was "very possible, very plausible" that the crisis would develop further after Putin's recognition of Donetsk and Lugansk's independence.

It added that Putin may also test the West's resolve in the Balkans, Bosnia, Transnistria in Moldova, and the Caucasus.

"We want each of these countries to be aware that there are choices to make, that partnership with the EU necessitates clarity," Elysee said.