White House Press Secretary Sean Spicer repeated on Tuesday that President Donald Trump believes millions of people voted illegally in the 2016 election, despite offering zero evidence in support of the claim.

CNN host Jake Tapper seemed in disbelief while covering the press conference later in the day, calling out the outlandish claim for what it is: a “fiction.”

“It is empirically a stunning allegation for which the White House is providing no evidence,” Tapper said during the breaking news segment. “And there is a reason they are providing no evidence. There is no evidence ― it is not true.”

You want to hear @jaketapper's thoughts on the president's allegations of massive voter fraud. pic.twitter.com/jXTJlm7uSY — Rob Bennett (@rob_bennett) January 24, 2017

Spicer failed to offer any evidence during the daily press briefing, telling reporters that Trump’s belief is “based on studies and evidence that people have presented to him,” but failing to mention any specifics.

Numerous news outlets and fact-checkers have investigated the claim, finding no evidence of widespread voter fraud in the 2016 election.

Still, Trump pushed his voter fraud conspiracy during his campaign, as well as after the election, stating that he would have won the popular vote if not for the “millions of people who voted illegally.”

In addition to winning the Electoral College in a landslide, I won the popular vote if you deduct the millions of people who voted illegally — Donald J. Trump (@realDonaldTrump) November 27, 2016

However, if Trump’s claims were even remotely true, Tapper said, “he would be derelict not to order a major investigation.”

“It would likely require a vast conspiracy involving public officials all over the country and would likely have had far-reaching impact in other contests, tainting races down the ballot ― not just the presidential race.”

“If President Trump’s beliefs are true,” Tapper added, “Republican leaders in congress should be holding hearings and trumpeting this injustice every single day.”

Despite his insistence on pushing this debunked claim, Trump does not appear to have many strong allies in it.

Senate Republicans dodged questions surrounding the claims on Tuesday, and even staunch Trump supporter Mike Huckabee said in an interview with Fox Business Network he is “not sure why [Trump] brought it up.”

Spicer likewise did not say whether he agreed with Trump during the press conference ― a telling detail, according to Tapper.

“[Spicer] did not say that he shared the belief, even after he was asked. Now, why would that be?” Tapper said. “Perhaps because there’s zero evidence of widespread voter fraud in the 2016 election. Now, has there ever been voter fraud? Any instances? Yes. Massive voter fraud? Three to 5 million votes cast illegally in 2016? No, it’s simply not true.”