Former President Jimmy Carter said Friday that he believes President Trump only won the 2016 election because Russia interfered to help him defeat Democratic nominee Hillary Clinton.

"There's no doubt that the Russians did interfere in the elections and I think the interference, although not yet quantified, if fully investigated would show that Trump didn't actually win the election in 2016," Carter said at an event in Leesburg, Va.

"He lost the election and he was put into office because the Russians interfered on his behalf," Carter said.

When asked by moderator and historian Jon Meacham if he believed Trump was then an "illegitimate" president, Carter replied: "Based on what I just said, which I can't retract."

The White House did not immediately return a request for comment on Carter's remarks Friday.

Former special counsel Robert Mueller found that Russia interfered in the 2016 election in "sweeping and systematic fashion" in order to help Trump prevail over Clinton. Neither Mueller nor the U.S. intelligence community has said that Russia's efforts, which included hacking Democratic organizations and spreading disinformation, contributed directly to Trump's election.

Mueller also did not find sufficient evidence to charge members or associates of Trump's campaign with conspiring with Russia to interfere in the vote.

"Although the investigation established that the Russian government perceived it would benefit from a Trump presidency and worked to secure that outcome, and that the Campaign expected it would benefit electorally from information stolen and released through Russian efforts, the investigation did not establish that members of the Trump Campaign conspired or coordinated with the Russian government in its election interference activities," states Mueller's 448-page report.

Trump has repeatedly cast doubt on the U.S. intelligence community's assessment that Russia interfered in the election in order to help his candidacy.

Following the conclusion of Mueller's two-year investigation, Trump tweeted in May that Russia helped his campaign during the election, only to walk back the remarks moments later.

"No, Russia did not help me get elected," Trump told reporters at the White House one day after Mueller delivered his first public remarks on the investigation.

Carter, who was participating in a discussion on human rights hosted by the Carter Center, said Friday that Trump should "condemn" Russian interference and "admit that it happened."

Carter's remarks came hours after Trump met with Russian President Vladimir Putin on the sidelines of the Group of 20 summit in Osaka, Japan.

Ahead of the meeting, journalists asked Trump if he would warn Russia not to meddle in future U.S. elections.

"Yes, of course, I will. Don't meddle in the election, please. Don't meddle in the election," Trump said, pointing to Putin and smiling.

Trump beat Clinton in the Electoral College 304 to 227, but lost the popular vote by nearly 3 million.