In the spring of 2016, longtime political operative Roger Stone had a phone conversation that would later seem prophetic, according to the person on the other end of the line.

Stone, an informal adviser to then-candidate Donald Trump, said he had learned from WikiLeaks founder Julian Assange that his organization had obtained emails that would torment senior Democrats such as John Podesta, then campaign chairman for Democratic presidential candidate Hillary Clinton.

The conversation occurred before it was publicly known that hackers had obtained the emails of Podesta and of the Democratic National Committee, documents which WikiLeaks released in late July and October. The U.S. intelligence community later concluded the hackers were working for Russia.

The person, who spoke to The Washington Post on the condition of anonymity because of the ongoing federal investigation into Russian campaign interference, is one of two Stone associates who say Stone claimed to have had contact with Assange in 2016.

The second, former Trump adviser Sam Nunberg, said in an interview on Monday that Stone told him that he had met with Assange — a conversation Nunberg said investigators for special counsel Robert Mueller recently asked him to describe.

Stone’s possible connection to Assange has been under scrutiny since the 2016 campaign, when he made public claims that he was in contact with the London-based WikiLeaks founder. Since then, Stone has emphatically denied any communication with Assange or advance knowledge of the document dumps by WikiLeaks, which embarrassed Clinton allies and disrupted the 2016 campaign. WikiLeaks and Assange also have said they never communicated with Stone.

Potential contacts with WikiLeaks have been probed by federal investigators examining whether allies of President Donald Trump coordinated with Russians seeking to tilt the 2016 race. The president has repeatedly denied any collusion with Russia.

Peter Carr, a spokesman for Mueller’s office, declined to comment.

Stone, a longtime Trump friend, briefly worked for his presidential campaign in 2015 and then remained in his orbit as an adviser.

In an interview on Monday, he again denied that he had any advance notice about the hacked emails or any contact with Assange. He said he only recalled having one conversation with anyone in which he alluded to meeting the WikiLeaks founder — a comment he said he made as a joke to a long-winded Nunberg.

“I wish him no ill will, but Sam can manically and persistently call you,” Stone said, recalling that Nunberg had called him on a Friday to ask about his plans for the weekend. “I said, ‘I think I will go to London for the weekend and meet with Julian Assange.’ It was a joke, a throwaway line to get him off the phone. The idea that I would meet with Assange undetected is ridiculous on its face.”’

Stone said he does not recall any similar conversation with anyone else.

“The allegation that I met with Assange, or asked for a meeting or communicated with Assange is provably false,” he said, adding he did not leave the country in 2016.

Through his attorney, Assange — who has been living in the Ecuadoran Embassy in London since 2012 — told The Post in January that he did not meet Stone in spring 2016.