President Donald Trump said on Monday he would want to know what Ukraine planned to do with US-made Tomahawk missiles before agreeing to supply them, Reuters reports.

Ukrainian President Volodymyr Zelenskyy has asked the US to sell Tomahawks to European nations that would send them to Ukraine.

Tomahawk missiles have a range of 2,500 km (1,550 miles), putting Moscow in the range of Ukraine's arsenal, were Kyiv to be granted them.

Asked by reporters at the White House whether he had decided about supplying Ukraine with Tomahawks, Trump did not rule it out and said he had "sort of made a decision" on the matter.

"I think I want to find out what they're doing with them," he said. "Where are they sending them? I guess I'd have to ask that question."

"I would ask some questions. I'm not looking to escalate that war," he added.

Russian President Vladimir Putin had said in a video clip released on Sunday that if Washington supplied Tomahawk missiles to Ukraine for long-range strikes deep into Russia, it would lead to the destruction of Moscow's relationship with Washington.