Trump, who took office on Jan. 20 for his second, non-consecutive White House term, has made allusions to seeking a third one but addressed it directly in a telephone interview with NBC News.

"No, I'm not joking. I’m not joking," Trump said, but "it is far too early to think about it."

"There are methods which you could do it, as you know," he said, declining to elaborate on specific methods.

US presidents are limited to two four-year terms, consecutive or not, according to the 22nd Amendment of the US Constitution.

A proposal to overturn a constitutional amendment requires a two-thirds vote in both houses of Congress and ratification by the legislatures of three-fourths of the 50 US states.

Some Trump allies have floated the idea of keeping Trump in the White House beyond 2028, and the president has also brought up the idea on a number of occasions in a manner that seemed to poke at his political opponents.

Trump, who at 78 was the oldest US president at the time of his inauguration, would be 82 if he took on another four-year term following the November 2028 election.

George Washington in 1796 set the precedent for a two-term presidency, a self-imposed limit that was observed by most US presidents for more than 140 years until Franklin D. Roosevelt in 1940.

Roosevelt, a Democrat who was president during the Great Depression and World War 2, broke tradition and served a third term, then died months into his fourth term in 1945. This paved the way for the amendment on term limits in 1951.

Longtime Trump adviser Steve Bannon said in a March 19 interview with NewsNation that he believes Trump will run again in 2028. Bannon said he and others are looking into ways to make that happen, including examining the definition of a term limit.

"We're working on it," Bannon said.