The various reports suggested potential outlines of a U.S. proposal that could include a ceasefire along current frontlines, U.S. recognition of Russia's annexation of Crimea, Russia's relinquishing claims to the four Ukrainian provinces and an international force to monitor a ceasefire.

President Volodymyr Zelenskiy said on Tuesday that Ukraine would be ready to hold talks with Russia in any format once a ceasefire is in place and the fighting between Kyiv and Moscow's forces has stopped.

An unusual public back-and-forth suggested that both sides in the war were eager to at least appear interested in negotiations.