Brian Dennehy, the veteran actor of stage and screen, died on Wednesday, his daughter Elizabeth said. He was 81.

“It is with heavy hearts we announce that our father, Brian passed away last night from natural causes, not Covid-related,” Elizabeth wrote on Twitter. “Larger than life, generous to a fault, a proud and devoted father and grandfather, he will be missed by his wife Jennifer, family and many friends.”

The tall, imposing Dennehy, who was born in Bridgeport, Conn., was a fixture at the movies in the 1980s and ’90s, appearing in such films as “First Blood,” “Tommy Boy” and “Cocoon.” Known for his big, tough-guy exterior, he also drew a following for playing Chicago detective Jack Reed in five TV movies.

A lesser-known role of Dennehy’s was as serial killer John Wayne Gacy in 1992’s “To Catch A Killer.” And when ESPN asked him about playing Bobby Knight in the biopic “Season on the Brink,” the spitfire was ready with an answer.

“People ask me, ‘How does it feel to play a real prick like Bobby Knight?’,” he said. “And I say, ‘Bobby Knight’s not a prick. John Wayne Gacy, he was a prick!’”

Although Dennehy continued to star in movies all the way through the 2018 comedy “Tag,” in recent years he became better known as an acclaimed stage performer, appearing on Broadway six times. Notably, he played Willy Loman in Arthur Miller’s “Death of A Salesman” in 1999 and James Tyrone in Eugene O’Neill’s “Long Day’s Journey Into Night” in 2003. He won the Best Actor Tony Award for both. Those productions began at the Goodman Theatre in Chicago, which was one of Dennehy’s artistic homes.

His last appearance on the New York stage was in “The Iceman Cometh” at BAM in 2015.

Director Robert Falls, who has been collaborating with Dennehy for 34 years, told The Post, “he considered his theater work everything. That’s what he was proud of, that’s what he lived for.”

Indeed, when The Post’s Barbara Hoffman asked Dennehy about tackling Loman, one of the American theater’s greatest roles, he gushed not about his own performance, but about Miller’s writing.

“I’ve seen college productions of ‘Death’ that would break your heart,” he said. “It doesn’t make any difference what your background is. Irish-American, Chinese-American — it speaks to all of us. It’s the great American play.”

[embedyt] https://www.youtube.com/watch?v=xgtDZm2lDcg[/embedyt]

Falls, who helmed “Salesman,” Long Day’s Journey,” “Iceman” and many other Dennehy-led shows added he was in awe of his friend’s galvanizing spirit all the way into old age.

“At age 75, here was a guy who was working at Stratford, working at the Goodman, and in one year was playing giant roles by Samuel Beckett, Pinter, Shakespeare and O’Neill,” Falls said. “He was hungry, and devoured these roles.”

Dennehy spent several seasons at the Stratford Festival in Ontario, Canada, starring in Shakespeare’s “All’s Well That Ends Well,” Harold Pinter’s “The Homecoming” and Beckett’s “Waiting for Godot,” among others. He even unleashed his inner rock-star in a music-driven production of “Twelfth Night” in 2011.

The actor with a good sense of humor caught up with The Post’s Cindy Adams in 2019.

“Truth is I haven’t got that kind of public appeal anymore anyhow. Most people think I’m dead 10 years,” Dennehy said. “I’m Irish. Don’t smoke. Maybe too much wine, but not like I used to, where I’d end up in strange company. Now, I drink just enough to make it to my own comfortable bed.”