Cartoonist Bill Leak has died aged 61 of a suspected heart attack.
"It's with a heavy heart that we report our editorial cartoonist Bill Leak has died," The Australian newspaper tweeted on Friday.
Leak won nine Walkley awards and 19 Stanley awards for his work.
He died in hospital, The Australian said on Friday.
Editor-in-chief "a giant in his field of cartooning and portraiture and a towering figure for more than two decades" at the newspaper.
Whitaker said Leak was "simply irreplaceable" and expressed his sympathy to the cartoonist's wife, Goong, stepdaughter Tasha and sons Johannes and Jasper.
Leak courted controversy throughout his career.
In a cartoon about Indigenous parental neglect published in The Australian in August 2016, Leak depicted a police officer telling an Aboriginal man holding a beer can to talk to his son about personal responsibility.
The Indigenous man replied: "Yeah righto. What's his name then?"
The cartoon was highly divisive, with a racism complaint lodged with the Human Rights Commission before it was subsequently dropped.
The Bill Leak cartoon that courted controversy. Source: The Australian
Conservative figures, including federal coalition politicians, that section 18C of the Racial Discrimination Act needed be changed.
The Spectator author Rowan Dean on Friday said his good friend had been "hounded to his grave".
"Bill was one of the most talented guys you will ever meet, one of the nicest guys you will ever meet," Dean told 2GB.
"No one worked harder than Bill, he was up at 4am every morning doing his cartoons, which are among the very, very best satirical work in Australia."
Dean pointed the finger at the "evil, evil" section 18C and the Human Rights Commission for hounding Leak for simply "doing his job".
He said a fatwah issued against the cartoonist for poking fun at the prophet Mohammed forced Leak to sell his house and live in a secret location.
"This man worked so hard caring for people and was genuinely concerned about our country," Dean said.
"(He was) determined to see the right things done by the right people and he has been hounded to his grave and it is disgusting."
