President Donald Trump’s former campaign manager Paul Manafort secretly met with WikiLeaks founder Julian Assange on multiple occasions, with the last meeting occurring a few months before WikiLeaks released hacked Democratic National Committee emails in the summer of 2016, The Guardian reported Tuesday.

Read the full Guardian report here.

Manafort met with Assange in 2013, 2015 and “around March 2016,” sources told The Guardian. Trump hired him at the end of March. The details of the meetings were unknown.

Manafort, in a statement issued through a representative, expressly denied meeting with Assange, called the story “totally false and deliberately libelous,” and said his team was considering “all legal options” against The Guardian.

“I have never met Julian Assange or anyone connected to him. I have never been contacted by anyone connected to Wikileaks, either directly or indirectly. I have never reached out to Assange or Wikileaks on any matter,” Manafort said.

WikiLeaks denied the report in a tweet, saying it “is willing to bet the Guardian a million dollars and its editor’s head that Manafort never met Assange.”

Remember this day when the Guardian permitted a serial fabricator to totally destroy the paper's reputation. @WikiLeaks is willing to bet the Guardian a million dollars and its editor's head that Manafort never met Assange. https://t.co/R2Qn6rLQjn — WikiLeaks (@wikileaks) November 27, 2018

On Monday, special counsel Robert Mueller, investigating Manafort as part of the larger probe into possible collusion between Trump’s campaign and Russia, said Manafort lied to investigators, violating his recent plea deal.

According to The Guardian, Manafort’s first meetings with Assange date back to 2012 and 2013, during his time as a pro-Russian lobbyist in Ukraine.

In August, a federal jury convicted Manafort for money laundering and tax evasion related to his lobbying work. A month later, he agreed to cooperate with Mueller’s investigators. But in court documents on Monday, Mueller’s team said Manafort recently violated the terms of the agreement by lying to federal prosecutors.

In response, Manafort’s attorneys said the complaint is invalid.

Jonathan Ernst/Reuters Former Trump campaign chairman Paul Manafort (right) secretly met with WikiLeaks founder Julian Assange on multiple occasions, according to The Guardian.

Trump responded to the news Tuesday by lashing out at Mueller and accusing him of being “a conflicted prosecutor gone rogue,” and again proclaiming the investigation a “Witch Hunt.”

During his campaign, Trump repeatedly touted the hacked WikiLeaks emails, and in July 2016, called on Russia to “find the 30,000 emails that are missing,” referring to opponent Hillary Clinton’s emails on her personal server. The same day, Russian hackers targeted her personal email, according to the timeline established by Mueller’s indictments this summer.

This story has been updated with additional background and Manafort’s and WikiLeaks’ response.

CORRECTION: A previous version of this story said a federal grand jury convicted Manafort in August. It was a federal jury, not grand jury, that convicted him.