US President Joe Biden convened a virtual meeting of allies Tuesday to discuss the Ukraine conflict, the White House said, after Kyiv announced Russia had launched a major new offensive in the country's east.

The meeting, announced on Biden's schedule, "is part of our regular coordination with allies and partners in support of Ukraine," an official told AFP.

The videoconference kicked off just before 10:00 am (1400 GMT) and brought together the leaders of France, Britain, Germany, Romania, Poland, Italy, Canada and Japan.

NATO chief Jens Stoltenberg also took part in the call, as well as the presidents of the European Commission and the European Council, Ursula von der Leyen and Charles Michel, according to the White House.

The meeting was to address "efforts to hold Russia accountable," the White House said.

The videoconference comes after Ukrainian President Volodymyr Zelensky said Russia, which invaded its pro-Western neighbor on February 24, recently launched a large-scale offensive in the eastern Donbas region, a move predicted by Kyiv for weeks.

Fighting has intensified in eastern Ukraine after Russia withdrew troops from the region around the capital Kyiv and refocused its efforts in Donbas, which pro-Moscow separatists have partly controlled since 2014.

The United States and Western allies have heaped pressure on Moscow via sanctions, while supporting Ukraine through military and other aid.

Asked Monday whether new measures would soon be announced, US State Department spokesman Ned Price said Washington would "continue to escalate our financial sanctions and other economic measures against the Russian Federation until and unless Moscow relents in its campaign against Ukraine."

"We have not yet seen that, and we'll continue to raise the costs," Price said.