US President Barack Obama on Wednesday had an Oval Office meeting with Hillary Clinton's Democratic primary rival Bernie Sanders, after which Sanders called Obama "even-handed" in the Democratic race for the White House.

"There was some discussion the other day about a Politico interview where he (Obama) was tipping the scales towards Secretary Clinton," Sanders told reporters after the 45-minute meeting. "I don't believe that at all."

"He (Obama) and the vice president had tried to be fair and even-handed in the process and I expect that will continue to be that way," Sanders added.

The rare Oval Office meeting came only two days after the US daily Politico published an interview with Obama, in which Obama showered praise on his former secretary of state.

"She (Clinton) can govern, and she can start here, day one, more experienced than any non-vice president has ever been who aspires to this office," said Obama, a remark widely interpreted by observers as a tacit endorsement of Clinton.

For Sanders, Obama said in the interview that Sanders had enjoyed the "luxury of being a complete long shot," a benefit that had spared him of intense scrutiny.

Though Sanders on Wednesday noted after his meeting with Obama that the president campaigned for him and he himself "did my best to see that he (Obama) would be elected president...as I did in 2012," the relation between the two men was not close.

During his career in politics, Sanders, a US senator from the state of Vermont had been a vocal critic of the Obama administration's failure to detail any plans to rein in Wall Street.

Shortly after the United States reached the Trans-Pacific Partnership deal with 11 other countries in the Pacific Rim under the auspices of Obama last October, Sanders bashed the trade agreement as "disastrous".

Also, unlike Clinton and her team staff, who had regular contact with Obama and his White House aides, the last time for Sanders to pay a solo visit to Obama in the Oval Office was on Dec. 15, 2014.