The United States has "paused" intelligence sharing with Ukraine after a dramatic breakdown in relations between Kyiv and the White House, CIA director John Ratcliffe said Wednesday.

President Donald Trump and Ukraine's leader Volodymyr Zelensky had a public falling-out in the Oval Office last week, followed by Ukraine's top ally suspending crucial US military aid.

Ratcliffe confirmed that intelligence sharing had also been frozen as Ukraine seeks to beat back the Russian invasion.

"President Trump had a real question about whether President Zelensky was committed to the peace process," Ratcliffe told Fox Business.

Ratcliffe said the pause "on the military front and the intelligence front" was temporary, and he expected that the United States will again "work shoulder to shoulder with Ukraine" in the future.

For Ukraine's armed forces, US intelligence is as important as military supplies in bloody fighting against the Russian offensive, and many ordinary Ukrainians have been shocked by Trump cutting off assistance.

National Security Advisor Mike Waltz told reporters at the White House that "we have taken a step back and are pausing and reviewing all aspects of this relationship."

Trump said Tuesday that Zelensky told him Kyiv was ready for talks with Moscow and the finalization of a US minerals access deal, as Ukraine works to move on after the Oval Office spat.

Zelensky has sought to bring Trump back onside, saying their clash was "regrettable" and he wanted "to make things right."

In his address to US Congress later on Tuesday, Trump read aloud from a letter from Zelensky saying "Ukraine is ready to come to the negotiating table as soon as possible to bring lasting peace closer."