The pardon comes at a moment when the president faces an escalating special counsel investigation of his own. A source in the White House said on Thursday that Trump was considering a pardon. Trump has called that probe a "witch hunt".
In a statement, the president said he doesn't know Scooter Libby, but heard for years that he had been mistreated.
Libby, a top aide to Cheney throughout the runup and ancient decades of this Iraq war, was found responsible in 2007 of lying and obstructing an investigation into who blew the cover of a Central Intelligence Agency officer, Valerie Plame, whose husband, former diplomat Joe Wilson, had criticized the Iraq war. President George W. Bush later commuted Libby's 30-month prison sentence but didn't issue a pardon despite intense pressure from Cheney.
Trump plans to pardon Libby. A federal pardon would simply move their prosecution beyond Mr. Trump's control. He is innocent, and he and his family have suffered for years because of his wrongful conviction.
The person said the pardon has been under consideration at the White House for months. He had already been reinstated to the bar by the District of Columbia Court of Appeals.
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The joint military campaign drew a swift and harsh response from Russian Federation , a key Syrian ally and its strongest partner. It was evident early on that Trump was intent on taking action to punish the Syrian regime for its actions.
Another twist is that the special counsel, Patrick Fitzgerald, was appointed by James Comey, deputy attorney general at the time.
That's according to a person familiar with the president's decision who said the announcement could come as early as Friday.
Libby's attorneys, Joseph diGenova and Victoria Toensing, issued a statement thanking Trump for "addressing a gross injustice" they said was inflicted by Fitzgerald and Comey.
What do you think of Scooter Libby's pardon? "I am grateful today that President Trump righted this wrong by issuing a full pardon to Scooter, and I am thrilled for Scooter and his family".
"Mr. Libby's case has always been a cause for conservatives who maintained that he was a victim of a special prosecutor run amok, an argument that may have resonated with the president".
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The latest set of cuts come in the wake of a weak United Kingdom market, with Jaguar sales down 26 per cent so far this year, compared with last year, while demand for Land Rovers in Britain is down 20 per cent.
"It hasn't been done through the normal channels".
Lewis Libby, Jr., also known as Scooter Libby. "This is a sad moment for our democracy and justice system".
Plame appeared on MSNBC Friday morning, saying a pardon would send a message "that you can commit crimes against national security and you will be pardoned".
Trump released a statement through the White House that he did not personally know Libby but that the man had been treated unfairly.
The pardon was the third for Mr Trump.
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Jutanugarn tied for third, five back, with top-ranked Feng Shanshan (71) and third-ranked Park Inbee (72), who bogeyed the last two holes.