US President Joe Biden warned that likely 2024 rival Donald Trump would contest the result of November's election if he loses, in an interview published Monday.

"Losers who are losers are never graceful," Biden was quoted as saying in a lengthy profile by the New Yorker magazine of the 81-year-old Democrat.

"I just think that he’ll do anything to try to win. If -- and  when -- I win, I think he’ll contest it," Biden added in the interview conducted in January.

Former president Trump, 77, the Republican frontrunner for his party's nomination as he bids for a comeback to the White House, falsely contends that Biden did not win the 2020 election.

Trump faces federal criminal charges of conspiring to overturn the vote four years ago, relating to the January 6, 2021 assault on the Capitol by a mob of his supporters.

In the New Yorker interview, Biden defended his decision to run for a second term despite polls showing voters are increasingly concerned about the Democrat’s age.

"If you thought you were best positioned to beat someone who, if they won, would change the nature of America, what would you do?" Biden told the magazine.

Trailing Trump in a series of recent polls and with his economic successes so far failing to register with voters, Biden has increasingly focused on attacking Trump as a threat to democracy.

Biden dismissed concerns that his campaign was overconfident, saying the media had written him off in 2020 against Trump and then again in mid-term and off-year elections in 2022 and 2023 -- all of which brought gains for him and the Democrats.

"I’m the only one who has ever beat him. And I’ll beat him again," he said.