Washington (CNN) President Donald Trump mentioned his presidential pardoning powers and condemned intelligence leaks in a string of tweets Saturday morning, a day after The Washington Post reported that Attorney General Jeff Sessions spoke about the Trump campaign in meetings with the Russian ambassador last year.

The Post reported Friday night that Russian Ambassador to the US Sergey Kislyak was previously picked up in US intelligence intercepts telling his Russian colleagues that he talked with Sessions twice last year about the campaign. Sessions, who was a campaign adviser at the time of his meetings with Kislyak, has repeatedly denied that he discussed the campaign with any Russians. His office has also denied he ever spoke with Kislyak about campaign interference.

In his Saturday morning tweets, the President referenced the fact that he holds presidential pardoning powers, saying , "While all agree the U. S. President has the complete power to pardon, why think of that when only crime so far is LEAKS against us. FAKE NEWS."

The Washington Post reported Thursday that Trump has asked his advisers about his power to pardon aides, family members and even himself in connection with the Justice Department's probe into Russia's efforts to influence last year's election, which is being led by special counsel Robert Mueller.

Friday morning, John Dowd, the attorney defending Trump in the Mueller investigation, called the Post story about Trump considering pardons "nonsense."

"The President's lawyers are cooperating with special counsel Robert Mueller on behalf of the President," Dowd added.

Brian C. Kalt is a professor of law at Michigan State University and the author of a 2012 book entitled "Constitutional Cliffhangers: A Legal Guide for Presidents and Their Enemies," told CNN that the presidential pardoning power is, in fact, very broad. The Constitution reads that the president "shall have power to grant reprieves and pardons for offenses against the United States, except in cases of impeachment."

In his Saturday tweets, Trump also launched into criticism of the Russia probe, asking why Sessions and Mueller weren't looking into Hillary Clinton's handling of classified information in emails while secretary of state and accusing her of having ties to Russia.

So many people are asking why isn't the A.G. or Special Council looking at the many Hillary Clinton or Comey crimes. 33,000 e-mails deleted? — Donald J. Trump (@realDonaldTrump) July 22, 2017

Clinton spokesman Nick Merrill did not immediately respond to a request for comment Saturday.

Trump also tweeted a defense of his eldest son, Donald Trump Jr., over his posting emails on Twitter earlier this month showing him setting up a meeting last summer with a Russian lawyer, Trump's son-in-law Jared Kushner and then-campaign chairman Paul Manafort with the aim of getting information that would be damaging to Clinton's campaign.

"My son Donald openly gave his e-mails to the media & authorities whereas Crooked Hillary Clinton deleted (& acid washed) her 33,000 e-mails!," Trump tweeted

Earlier, in the wee hours of the morning, the President referred to the Post report in a tweet, saying leaks of intelligence information, "like Comey's," must stop.

It was an apparent reference to fired FBI Director James Comey's testimony in June that he gave a memo about his interactions with Trump to a friend and Columbia Law School professor, the contents of which the friend, Daniel Richman, shared with The New York Times. Richman, a former federal prosecutor, has told CNN that the memo was not classified.

"A new INTELLIGENCE LEAK from the Amazon Washington Post, this time against A.G. Jeff Sessions," Trump wrote. "These illegal leaks, like Comey's, must stop!"

Justice Department spokeswoman Sarah Isgur Flores said in a statement to CNN that she could not comment on the Post's report Friday.

"Obviously I cannot comment on the reliability of what anonymous sources describe in a wholly uncorroborated intelligence intercept that the Washington Post has not seen and that has not been provided to me," she said. "But the attorney general stands by his testimony from just last month before the Senate Intelligence Committee, when he specifically addressed this and said that he 'never met with or had any conversations with any Russians or any foreign officials concerning any type of interference with any campaign or election.'"