Corsi said he had been offered a deal if he pleaded guilty and cooperated with Trump-Russia investigators

This article is more than 1 year old

This article is more than 1 year old

A prominent rightwing conspiracy theorist with links to a longtime ally of Donald Trump claimed on Monday he had rejected a plea deal offered by the special counsel Robert Mueller.

'America's straightest arrow': Robert Mueller silent as urgency mounts Read more

Jerome Corsi, who has connections to the Trump adviser Roger Stone, told MSNBC he had been offered a deal if he pleaded guilty and cooperated with investigators, but had resolved not to take it.

The NBC producer Anna Schecter tweeted that Corsi told her he had been offered a deal on one count of perjury. According to Schecter, he said: “They want me to say I willfully lied. I’m not going to agree that I lied. I did not. I will not lie to save my life. I’d rather sit in prison and rot for as long as these thugs want me to.”

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The proposed deal would take Mueller’s investigation a step closer to unravelling the connections between Russian hackers who stole Democratic party emails, WikiLeaks which published thousands them, and the Trump presidential campaign, which has faced questions of collusion after apparently having advance knowledge of the leak.

Corsi, 72, told the Guardian last week: “I can confirm that we have entered plea negotiations.”

Corsi is a former Washington bureau chief for the conspiracist website InfoWars.com and a leading proponent of the claim that Barack Obama was not born in the US and was thus not eligible to be president. Stone, 66, is a political operative and self-proclaimed “dirty trickster” who worked for Richard Nixon.

During the 2016 election, Stone boasted on social media and in interviews about his knowledge that WikiLeaks was about to hit Hillary Clinton’s campaign with damaging leaks. Days before WikiLeaks started rolling out hacked emails from the Clinton campaign chief John Podesta, Stone tweeted that “it will soon be Podesta’s time in the barrel”.

He has denied suggestions Corsi was his conduit for knowledge about WikiLeaks. But Corsi confirmed to the Guardian earlier this month that his contact with the WikiLeaks founder Julian Assange had been the focus of the Mueller team’s questions.

“The issue they went to over and over and over again was: who was my source with Assange?” he said.

According to the New York Times, prosecutors presented Corsi with evidence based on text messages and emails that he had not been truthful about his prior knowledge of the WikiLeaks dump of stolen emails.

The latest twists came on a day when the Mueller investigation was moving forward on several fronts.

The former Trump policy aide George Papadopoulos arrived at a federal correctional institution in Oxford, Wisconsin to begin his two-week sentence after a judge rejected a last-minute attempt to delay his incarceration.

Papadopouloswas sentenced in September for lying to the FBI in the Russia investigation. He had sought a postponement of his prison term until an appeals court rules in a separate case challenging the constitutionality of Mueller’s appointment.

But in a 13-page opinion on Sunday, US district court judge Randolph Moss said Papadopoulos had waited too long to contest his sentence.

Papadopoulos triggered the initial Russia investigation. Memos written by House Republicans and Democrats and now declassified show information about Papadopoulos’s contacts with Russians set in motion the FBI’s investigation in July 2016 into potential coordination between Russia and the Trump campaign.

That investigation – kept secret by the FBI until after the election – was taken over by Mueller when the FBI director, James Comey, was fired by Trump.

Mueller’s team was also due on Monday to update a judge on the status of the former Trump campaign chair Paul Manafort’s cooperation with investigators.

Manafort was found guilty of bank and tax fraud charges in one trial, then pleaded guilty to charges including money laundering and tax fraud related to acting as an unregistered agent of a foreign government.

He is due to be sentenced on 8 February, but that hinges on whether he is still working with investigators and whether they might need to call him as a witness in a new prosecution.

In Washington, Trump returned from Thanksgiving to complain bitterly about the Mueller investigation and its failure to talk to “hundreds of people closely involved with my campaign who never met, saw or spoke to a Russian”.

The president insisted that in his final report, Mueller should admit “all of his conflicts of interest”. He did not detail what he believes those conflicts are.