LEGENDARY insult comic Don Rickles, who earned a whole new generation of fans as Mr Potato Head in Toy Story, has died aged 90.

The 90-year-old icon had been in failing health and recently cancelled a May 6 show at the River Spirit Casino Resort in Tulsa.

The cause of death was kidney failure, his publicist said.

The salty-tongued funnyman was a favourite on The Tonight Show Starring Johnny Carson and The Late Show with David Letterman.

But young fans also knew him as Mr. Potato Head on Toy Story.

For more than half a century, Rickles headlined casinos and nightclubs from Las Vegas to Atlantic City, New Jersey, and livened up late-night talk shows.

No one was exempt from Rickles' insults, not fans or presidents or such fellow celebrities as Frank Sinatra, Dean Martin and Johnny Carson.

Some of the best Don Rickles moments

Despite jokes that from other comics might have inspired boycotts, he was one of the most beloved people in show business, idolised by everyone from Joan Rivers and Louis CK to Chris Rock and Sarah Silverman.

James Caan once said that Rickles helped inspire the blustering Sonny Corleone of The Godfather.

The final tweet Rickles posted was a message to his wife of 52 years, Barbara.

"We are celebrating our 52nd Wedding Anniversary March 14th. Happy Anniversary my dear wife, Barbara. You are my life,' he wrote, signing off 'XO Pussycat (me)"

An HBO special was directed by John Landis of Animal House fame and included tributes from Clint Eastwood, Sidney Poitier and Robert De Niro.

Carl Reiner would say he knew he had made it in Hollywood when Rickles made fun of him.

Rickles patented a confrontational style that stand-up performers still emulate, but one that kept him on the right side of trouble.

He emerged in the late 1950s, a time when comics such as Lenny Bruce and Mort Sahl were taking greater risks, becoming more politicized and more introspective.

Rickles managed to shock his audiences without cutting social commentary or truly personal self-criticism.

He operated under a code as old the Borscht Belt: Go far - ethnic jokes, sex jokes, ribbing Carson for his many marriages - but make sure everyone knows it's for fun.

"I think the reason that (my act) caught on and gave me a wonderful career is that I was never mean-spirited," he once said. "Not that you had to like it, but you had to be under a rock somewhere not to get it."