Former Mayor Ed Koch, the combative, outspoken politician who rescued New York City from near-financial ruin during an 11-year run as the city's leader has died at the age of 88, his spokesperson has said.
Koch died of congestive heart failure at about 2am local time (07:00GMT) at New York-Presbyterian hospital following a year of repeated hospitalisations, George Arzt, his spokesman, said on Friday.
A witty and larger than life figure, Koch, who remained a frequent public presence up to his last days, had been suffering heart and other health problems.
Michael Bloomberg, the current mayor, praised Koch as a "tireless, fearless and guileless civic leader" for his role in pulling New York back from the brink of financial collapse in the late 1970s and 1980s.
"Ed helped lift the city out of its darkest days and set it on course for an incredible comeback," Bloomberg said, ordering flags to be lowered to half-mast.
Koch's greatest success was in his tough financial management during three terms between 1978 and 1989, but he also presided over an era when AIDS, homelessness, crime and racial tensions were rampant in the Big Apple.
More than anything Koch is remembered for his salty and colorful New Yorker style and sense of humor.
He frequently walked in public or stood outside subway stations, earning a reputation as man of the people. "How'm I doin'?" was his trademark greeting to voters.
'I punch back'
The Jewish son of Polish immigrants was quick with a friendly quip and equally fast with a cutting remark for his political enemies.
"You punch me, I punch back," Koch once memorably observed. "I do not believe it's good for one's self-respect to be a punching bag."
Civil rights activist the Reverend Al Sharpton said in a statement on Friday that although they disagreed on many things, Koch "was never a phony or a hypocrite. He would not patronise or deceive you. He said what he meant. He meant what he said. He fought for what he believed. May he rest in peace."
When mayor, Koch often dismissed his critics as "wackos", waged verbal war with developer Donald Trump (whom he called "piggy") and mayoral successor Rudolph Giuliani (who Koch refered to as a "nasty man"), lambasted civil rights leader the Reverend Jesse Jackson, and once reduced the head of the city council to tears.
"I'm not the type to get ulcers," he wrote in 'Mayor', his autobiography. "I give them."
When President George W Bush ran for re-election in 2004, Koch, a Democrat, crossed party lines to support him and spoke at the Republican convention. He also endorsed current Mayor Michael Bloomberg's re-election efforts at a time when Bloomberg was a Republican. Koch described himself as "a liberal with sanity".
Koch was also an outspoken supporter of Israel, willing to criticise anyone, including President Barack Obama, over decisions Koch thought could indicate any wavering of support for that nation.
Koch was also a champion of gay rights, taking on the Roman Catholic Church and scores of political leaders on the issue.