President Biden doesn’t mince words when discussing his aversion to his predecessor Donald Trump behind closed doors.

Biden, 81, has referred to Trump, 77, as a “sick f–k” in conversations with his close aides and longtime friends, according to Politico. 

“What a f–king a–hole the guy is,” Biden has also recently said of the former president, the outlet reported.

The president’s distaste for Trump stems from his perception that his likely opponent in the November general election “delights in others’ misfortunes” and presents a clear and present danger to democracy through his “encouragement of political violence.” 

Accounts of Trump gleefully watching rioters storm the US Capitol on Jan. 6, 2021, from his private White House dining room particularly enrage Biden, the report notes. 

As does the affectionate language Trump deploys when discussing Russian President Vladimir Putin, and the former president’s 2017 remarks about there being “very fine people on both sides” after clashes between white supremacists and protesters in Charlottesville, Va.

Biden also fumed at reports that Trump refused to visit a military cemetery during inclement weather and that he has mocked US soldiers killed in action. 

The president’s loathing for Trump has only swelled as his predecessor gets closer to locking up the GOP nomination, the report notes. 

A spokesman for the Trump campaign slammed Biden’s R-rated remarks about the 45th president.

“It’s a shame that Crooked Joe Biden disrespects the presidency both publicly and privately,” Chris LaCivita, a senior Trump campaign adviser, told The Post.

“But then again, it’s no surprise he disrespects the 45th President the same way he disrespects the American people with his failed policies.”

The White House did not respond to The Post’s request for comment.