WASHINGTON, D.C.: The US is pressuring Ukraine to be open to peace talks with Moscow, with a top Pentagon official saying Kyiv's forces will find it hard to recover all the territory Russia has captured in the war.

US Joint Chiefs Chairman General Mark Milley said Wednesday that US and allied support has not diminished, but added that Kyiv's success in countering Russia's invasion puts it in a better position to begin talks.

And last week, Milley compared the current situation to World War I, when the two sides ground to a stalemate within months but kept fighting for three more years at the cost of millions of lives.

He said Wednesday that the Russians are now reinforcing their hold on about 20 percent of Ukraine territory, and that the front lines from Kharkiv down to Kherson are stabilizing.

'The probability of a Ukrainian military victory, defined as kicking the Russians out of all of Ukraine, to include ... Crimea, the probability of that happening anytime soon is not high, militarily,' he said.

'There may be a political solution where, politically, the Russians withdraw, that's possible,' Milley added.

'You want to negotiate from a position of strength. Russia right now is on its back,' he said.

Spy chiefs meet