South Carolina Republican Sen. Lindsey Graham criticized President-elect Donald Trump for praising Julian Assange while expressing skepticism of alleged Russian hacking.

Trump tweeted early Wednesday, citing an interview the WikiLeaks founder did with Fox News on Tuesday in which he said a “14-year-old” could have hacked into the email account of John Podesta, Hillary Clinton’s campaign manager.

The president-elect also cited Assange’s assertion that the information from that hack and others of Democratic officials did not come from the Russians.

Julian Assange said “a 14 year old could have hacked Podesta” – why was DNC so careless? Also said Russians did not give him the info!

— Donald J. Trump (@realDonaldTrump) January 4, 2017

“@FoxNews: Julian Assange on U.S. media coverage: “It’s very dishonest.” #Hannity pic.twitter.com/ADcPRQifH9” More dishonest than anyone knows

— Donald J. Trump (@realDonaldTrump) January 4, 2017

Asked on CNN about Trump appearing to take the side of the WikiLeaks founder over that of the U.S. intelligence community, Graham said, “It’s very disturbing, quite frankly.” Graham said he would encourage Trump to be “doubtful” about Assange, and to ask some “hard questions” in an intelligence briefing the president-elect is scheduled to get on Friday.

Assange told Fox News’ Sean Hannity on Tuesday that the outgoing Obama administration is focusing on the hacking in an attempt to delegitimize the incoming Trump administration.

“I hope no American will be duped by him,” Graham said of Assange. “Look at his record in terms of how he treats our country.”

Graham also said that if Rex Tillerson, Trump’s pick for secretary of State, did not accept that Russia hacked into Democratic National Committee emails and those of Podesta, he would have a hard time voting for him.

“If a nominee for a critical job doesn’t understand what the Russians are up to, I’ll have a hard time believing they are good at their job,” he said.