Conrad Black, who wrote a book praising Donald Trump last year, has been pardoned in light of his "tremendous contributions to business", the White House said.
President Donald Trump on Wednesday pardoned disgraced British media mogul Conrad Black, who served more than three years in prison in the US for fraud and obstruction of justice.
Black, 74, a Canadian-born British citizen, once ran an international newspaper empire that included the Chicago Sun-Times, Britain's Daily Telegraph and the Jerusalem Post.
"Lord Black's case has attracted broad support from many high-profile individuals who have vigorously vouched for his exceptional character," the White House said in a statement announcing the pardon.
It said Black had made "tremendous contributions to business," had written books on history and served as a tutor while in prison.
"In light of these facts, Mr. Black is entirely deserving of this Grant of Executive Clemency," the White House said.
The office of Canadian Prime Minister Justin Trudeau declined to comment.
Black said Trump had called him to say that he would be granted a full pardon, that his conviction was "unjust" and that he "should never been charged".
"The idea that I would commit a crime is a nonsense," Black told the BBC. He said that he was now "rebuilding my fortune, life goes on, this is a great occasion".
Black, who has called Trump a friend, published a book last year praising him, titled "Donald J. Trump: A President Like No Other."
He was found guilty in the United States in 2007 of scheming to siphon off millions of dollars from the sale of newspapers owned by Hollinger Inc, where he was chief executive and chairman.
Black, a prolific writer and historian in his own right, vehemently maintained his innocence and launched a series of libel lawsuits in Canada to strike back at the detractors he blames for destroying his once vast empire.
But years of legal battles - which went all the way up to the US Supreme Court - failed to fully clear his name, although he did manage to greatly reduce his prison time by clearing himself of many of the charges.
Two of his three fraud convictions were later voided, and his sentence was shortened. He was released from a Florida prison in May 2012 and deported from the United States.
In 2013, the U.S. Securities and Exchange Commission banned Black from acting as a director of a U.S. company and ordered him to pay $4.1 million in restitution.
Canada's Ontario Securities Commission ruled in 2015 that Black could no longer hold executive positions at listed companies or investment funds
Trump has used his power of pardon before this and critics say he does it for people who back him or his ideas.
Reports have surfaced that he has considered pardoning people charged or convicted as part of the Russia election meddling probe.
Last year Trump granted a full pardon to Dinesh D'Souza, a conservative author and firebrand.
D'Souza pleaded guilty in 2014 to using fake donors to make political contributions to a Republican Senate campaign and ended up serving eight months in a halfway house in California.
In 2017, Trump pardoned Joe Arpaio, a former sheriff convicted of violating a court order to halt traffic patrols that targeted suspected unauthorised immigrants.