LEFT: US President Donald Trump. REUTERS/File; RIGHT: A special agent of the Federal Bureau of Investigation (FBI) investigates a scene in Queens, New York, US, March 25, 2010. REUTERS/Chip East/Files; SUPERIMPOSED: Former US President Bill Clinton and former US State Secretary Hillary Clinton in Manhattan, New York, US, January 6, 2015. REUTERS/Carlo Allegri/Files

WASHINGTON: The Federal Bureau of Investigation is probing the foundation of former president Bill Clinton amid pressure from President Donald Trump and allegations of corruption by Republican lawmakers, US media reported Friday.

The Hill, a news website covering Congress, CNN, and the New York Times all confirmed that Justice Department investigators are looking into issues involving donations to the Clinton Foundation in exchange for political favors while the ex-president´s wife, Hillary Clinton, was secretary of state from 2009-2013.

The Justice Department would not confirm the probe, but in November it informed House Judiciary Committee chairman Robert Goodlatte that Attorney General Jeff Sessions was evaluating the need for a probe into a controversial uranium deal that involved a major donor to the foundation.

The Clinton Foundation said it had already repeatedly proven such allegations wrong.

"Time after time, the Clinton Foundation has been subjected to politically motivated allegations, and time after time these allegations have been proven false. None of this has made us waver in our mission to help people," Foundation spokesman Craig Minassian said in a statement.

Nick Merrill, a spokesman for Hillary Clinton, told The Hill that the probe was "a sham" and said Sessions was "doing Trump´s bidding" by pursuing the case.

"This is a philanthropy that does life-changing work, which Republicans have tried to turn into a political football," Merrill said of the foundation.

Trump has, via Twitter and in speeches, repeatedly called for the Justice Department to reopen a probe into the private email server of Hillary Clinton, whom he defeated in the 2016 presidential election.

He also late last year raised the uranium deal several times. That involved the 2013 sale of Canadian mining company Uranium One to Russian state-owned company Rosatom, which was approved by former president Barack Obama.

The move gave Rosatom control of 20 percent of US uranium stockpiles, and was decided after Uranium One made sizable donations to the Clinton Foundation.

News of the investigation comes amid a stepped-up Republican campaign to undermine the investigation by independent special counsel Robert Mueller into alleged collusion between the Trump campaign and Russian interference in the 2016 election.

Mueller is also probing whether Trump sought to obstruct the Russia investigation.