US President Donald Trump said on Tuesday that he only wants to meet with Russian leader Vladimir Putin if a productive meeting can be expected.

Trump did not directly confirm media reports that a planned meeting with his Russian counterpart had been postponed. But when asked by a reporter what he knew about the alleged change in plans and whether it would affect his view on a potential sale of Tomahawk cruise missiles to Ukraine, he said he did not want"the meeting to be pointless."

"I don't want to waste any time, so I'll see what happens," Trump added in the Oval Office.

He said the decision had not yet been made. It was not clear whether he was referring to a possible meeting with Putin or the sale of long-range missiles to Ukraine. He said he would provide an update in the next two days and reiterated his view that any effort to end the war should freeze the front lines in Ukraine.

Several US media outlets have previously reported that Trump's planned meeting with Putin in Budapest is looking increasingly uncertain. The news website Politico, citing the White House, reported that the planned meeting in Budapest is no longer being held after US Secretary of State Marco Rubio spoke with Russian Foreign Minister Sergei Lavrov on Monday.

CNN, citing sources in the White House, also reported that the summit could be postponed; in addition, the preliminary meeting between Rubio and Lavrov, which is considered an important step before the presidential meeting, has also been postponed.

NBC News reported that Monday's phone call was"productive," but officials believe Russia and Ukraine are not ready for serious peace talks. The Washington Post also reported that a meeting is not planned in the near future.

Trump said on Thursday he wanted to meet Putin in Budapest to discuss the war in Ukraine. The US president did not give a date, but said shortly afterwards that it would be"probably in the next two weeks."