"Putin has occupied, illegally occupied, sovereign Ukrainian territory. He is not in any position to dictate to Ukraine what they must do to bring about peace," Pentagon chief Lloyd Austin said at the end of a NATO meeting in Brussels.

"He could end this today, if he chose to do that, and we call upon him to do that, and to leave Ukrainian sovereign territory."

Putin said Friday that Moscow would only halt its offensive on Ukraine if Kyiv effectively surrenders by pulling its troops out of the east and south and dropping its bid for NATO membership.

Ukraine immediately rejected Putin's hardline "conditions" to halt the full-scale military offensive that he launched in February 2022, with Kyiv trying to corral international support at a major peace summit in Switzerland this weekend.

NATO chief Jens Stoltenberg also slammed the conditions set out by Putin for initiating Ukraine peace talks.

"This is not a proposal made in good faith," Stoltenberg told reporters.

"This is a proposal that actually means that Russia should achieve their war aims, by expecting that Ukrainians should give up significantly more land than Russia has been able to occupy so far," he said.

"This is a proposal of more aggression, more occupation and, and it demonstrates, in a way, that Russia's aim is to control Ukraine."