John Fetterman

Sen.John Fetterman says Larry David needs to change his stripes and get over himself ... using a 1980s movie reference to tell Larry it's ridiculous to be embarrassed over the UFC event at the White House.

The Senator from Pennsylvania Senator ripped the "Seinfeld" creator for recently saying the fights held on President Donald Trump's birthday on the South Lawn made him "embarrassed to be an American."

Fetterman's got 3 words for Larry ... and while the movie reference goes over Jacob's head, what the Senator is trying to get across here is that the UFC event isn't un-American and Larry needs to get over himself.

For those in Jacob's boat ... "Lighten up, Francis" is a famous line from the Bill Murray flick "Stripes." The 45th anniversary of its premiere is this Friday and it seems Fetterman's a fan.

In the movie, one of the men in Bill's platoon threatens to kill his squad mates if they touch his belongings or call him Francis -- his Christian name -- instead of "Psycho." Warren Oates' character, U.S. Army Sergeant Hulka, responds to the diatribe with a wry "Lighten up, Francis."

Movie refernces aside ... Fetterman adds he's proud to be American ... and he thinks it's silly for Larry to be so upset over a UFC fight.

Larry's not alone in his outrage ... tons of people on the left didn't appreciate the event going down at the White House -- though Trump administration lawyers argued in court docs it's really not any different than the dozens of athletic events held there before.

Fetterman's not siding with his fellow Democrats here, though ... and it will be interesting if Larry fires back with a witty comeback.