WASHINGTON • Former US House Speaker John Boehner has let fly with a stunning critique of fellow Republican and presidential hopeful Ted Cruz, labelling him the devil incarnate.

"Lucifer in the flesh" is how the ever-blunt Republican heavyweight - who stepped down as Speaker last year - described the Texas senator, who is struggling to block billionaire Donald Trump's march to the Republican presidential nomination, according to the Stanford Daily newspaper.

"I have Democrat friends and Republican friends," Mr Boehner said. "I get along with almost everyone, but I have never worked with a more miserable son of a bitch in my life."

In an audio recording of the stunning remarks played on a loop on US television on Thursday, Mr Boehner is heard to add about Mr Cruz: "Over my dead body will he be president."

Mr Boehner's comments were made at a public talk late on Wednesday at Stanford University in Palo Alto, California.

An affronted Mr Cruz, fighting in Indiana to keep his presidential bid alive, responded that he barely knew Mr Boehner. "If I have said 50 words in my life to John Boehner, I'd be surprised, and every one of them has consisted of pleasantries," Mr Cruz told reporters, noting that he had never really worked with Mr Boehner.

"When John Boehner calls me Lucifer, he's not directing that at me. He's directing that at you," he said, alluding to his conservative supporters. "What Boehner is angry with me for is standing with the American people, is energising and encouraging House conservatives to stand with the American people and actually honour the commitments we have made," he said.

Many of Mr Cruz's enemies - including some from his own Republican Party - were quick to line up with Mr Boehner in showing their disdain for the ambitious Texas lawmaker who has done little to endear himself to fellow lawmakers.

Mr Charlie Dent, a Republican congressman from Pennsylvania, said that as far as he was concerned, Mr Boehner's description of Mr Cruz was just about right.

"All I can say is somebody should contact Lucifer for comment - he may be upset about these remarks," he told MSNBC.

AGENCE FRANCE- PRESSE, NEW YORK TIMES

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