Bennett was the last of the great saloon singers, whose devotion to classic songs graced a decades-long career.

Bennett’s publicist, Sylvia Weiner, confirmed his death on Friday, saying he passed away in his hometown of New York, The Associated Press news agency reported. Weiner gave no specific cause, but Bennett had been diagnosed with Alzheimer’s disease in 2016.

Bennett was born Anthony Dominick Benedetto in the Astoria neighbourhood of the New York borough of Queens.

His ceaselessly cheery spirit bridged generations to make him a hit maker across seven decades, including the enduring I Left My Heart in San Francisco.

Frank Sinatra, another legendary US singer, called the former singing waiter “the best singer in the business” after he became a star in the 1950s. Bennett went on to win 20 Grammy awards, including a lifetime achievement award.

Bennett’s career was filled with highs and lows.

He was in his 50s in the late 1970s when he found himself facing a decaying marriage, a cocaine habit, a $2m tax debt and limited career prospects. He pulled out of it by turning over his management to his son Danny, who propelled his father to new heights of popularity by introducing him to younger generations.

The older he grew, the more diverse his collaborators became. Bennett was in his late 80s when he recorded a 2014 album of duets with pop star Lady Gaga and went on a world tour with her in 2015. Partners on his popular Duet albums ranged from former Beatle Paul McCartney and soul queen Aretha Franklin to country star Willie Nelson and U2’s Bono.

“Tony Bennett has not just bridged the generation gap, he has demolished it,” The New York Times said in 1994. “He has solidly connected with a younger crowd weaned on rock. And there have been no compromises.”

His renditions of old classics – such as Stranger in Paradise, The Way You Look Tonight, Rags to Riches, I Wanna Be Around, The Lady Is a Tramp, and Body and Soul – appealed to millions of young people.

Bennett marked his 90th birthday in 2016 with a party in New York that drew celebrities such as Hollywood actors Bruce Willis and John Travolta. The Empire State Building put on a light show in his honour. He also published a memoir in 2016 titled Just Getting Started.

Bennett revealed in early 2021 that he had been diagnosed with Alzheimer’s Disease five years earlier, but he kept recording after the diagnosis and later tweeted, “Life is a gift – even with Alzheimer’s.”

Due to his illness, Bennett retired from performing after his final concerts at Radio City Music Hall on August 3 and 5, 2021.