William Cummings

USA TODAY

Donald Trump repeated his skepticism of the U.S. intelligence community's conclusion that Russia was behind cyberattacks meant to influence the presidential election in a tweet Tuesday announcing that an intelligence briefing on the matter had been delayed until Friday.

"The 'intelligence' briefing on so-called 'Russian hacking' was delayed until Friday, perhaps more time needed to build a case. Very strange!" the president-elect tweeted.

NBC and CNN, citing intelligence officials, said the meeting had always been scheduled for Friday.

Several commentators noted that Trump's use of quotation marks in the tweet appeared intended to mock the reliability of the American intelligence community.

On New Year's Eve, Trump expressed more doubts about the intelligence community's conclusions about Russia.

"I want them to sure," Trump told reporters. "I think it's unfair if they don't know. And I know a lot about hacking. Hacking is a very hard thing to prove, so it could be somebody else. And I also know things that other people don't know and so they can not be sure of this situation."

Trump said he would give more detail on "the things that other people don't know" on Tuesday or Wednesday.