Ukraine's President Volodymyr Zelenskyy asks for evidence on new invasion warnings

Ukraine's President Volodymyr Zelenskyy played down intensified warnings of a possible Russian invasion within days, saying he had yet to see convincing evidence.

Ukraine's president played down intensified warnings of a possible Russian invasion within days, saying he had yet to see convincing evidence, even as the US warned Sunday of more Russian troops pressing closer to Ukraine's borders and some airlines cancelled or diverted flights there.

The White House said President Joe Biden would talk later in the day with Ukrainian President Volodymyr Zelenskyy.

The Ukrainian leader's repeated statements urging calm among his people — while Russian forces surround Ukraine on three sides in what Russia insists are military exercises -- grew this weekend to Zelenskyy questioning strident warnings from US officials in recent days that Russia could be planning to invade as soon as midweek.

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The US picked up intelligence that Russia is looking at Wednesday as a target date, according to a US official familiar with the findings. The official, who was not authorised to speak publicly and did so only on condition of anonymity, would not say how definitive the intelligence was.

“We're not going to give Russia the opportunity to conduct a surprise here, to spring something on Ukraine or the world,” Jake Sullivan, the US national security adviser, told CNN on Sunday, about the US warnings.

“We are going to make sure that we are laying out for the world what we see as transparently and plainly as we possibly can," he said.