Washington (CNN) President Donald Trump on Friday mocked the two-week prison sentence given to former campaign adviser George Papadopoulos who pleaded guilty to lying to the FBI about his contact with Russian operatives before the 2016 election, despite declaring hours earlier: "I don't know him."

Papadopoulos, who was sentenced to 14 days in jail, is the first Trump adviser to be sentenced as part of special counsel Robert Mueller's investigation into Russian interference in the 2016 election and potential collusion between the Kremlin and the campaign.

14 days for $28 MILLION - $2 MILLION a day, No Collusion. A great day for America! — Donald J. Trump (@realDonaldTrump) September 7, 2018

Shortly after his sentence, the President weighed in on Twitter: "14 days for $28 MILLION - $2 MILLION a day, No Collusion. A great day for America!"

He did not elaborate on the $28 million price tag he cited, though it appeared to be about the cost of Mueller's investigation. Even that, however, is incorrect. The Justice Department has spent at least $17 million investigating Russian meddling, but government estimates have shown that Mueller's team specifically has only spent about $7.7 million.

But the tweet illustrated how closely the President and his team were following the sentencing hearing today in Washington. Speaking to reporters aboard Air Force One on Friday afternoon, Trump distanced himself from Papadopoulos.

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