Roger Stone, former advisor to President Donald Trump, arrives with his wife Nydia Stone (R) and his legal team for the second day of his trial at the E. Barrett Prettyman United States Courthouse on November 6, 2019 in Washington, DC.

Gates testified in U.S. District Court in Washington, D.C., that less than a minute after finishing a July 2016 call from Stone, Trump indicated that "more information would be coming" from Wikileaks.

That testimony by Rick Gates at Stone's trial contrasts with Trump's claim last November that he did not recall speaking to Stone about WikiLeaks, the document disclosure group that during the 2016 campaign released emails stolen from the Democratic Party and Democratic presidential nominee Hillary Clinton's own campaign chief.

A former top Trump campaign official on Tuesday testified that President Donald Trump talked to political trickster Roger Stone about WikiLeaks during the 2016 campaign.

In a written response to special counsel Robert Mueller last November, Trump had said, "I do not recall discussing WikiLeaks with" Stone, "nor do I recall Mr. Stone having discussed WikiLeaks with my campaign."

But Trump also said, "I was aware that WikiLeaks was the subject of media reporting and campaign-related discussion at the time."

The president's written responses were requested by Mueller last year as part of his probe of Russian interference in the 2016 presidential election, and the question of whether Trump's campaign had coordinated with Russians.

Gates testified Tuesday that in addition to speaking to Trump about WikiLeaks, Stone was known in the campaign as a source for information expected to be released by the group.

And Gates also testified that another campaign official, Paul Manafort, told him that he would update Trump with any information that he could get from Stone.

Jurors on Tuesday saw an email between Gates and Stone after the Democratic National Committee revealed that its computers had been hacked in 2016. U.S. intelligence agencies later said that hackers were Russian agents.

In that email, Stone asked Gates for the contact information of Jared Kushner, Trump's son-in-law and a senior advisor to the president.

WikiLeaks later ended up releasing emails stolen from the DNC during the campaign in an apparent effort to boost Trump's candidacy.

Jay Sekulow, a lawyer for Trump, declined to comment about Gates' testimony when contacted by CNBC.

Stone, a longtime Republican operative and friend of Trump's, is charged with lying to Congress about his contacts with WikiLeaks during the 2016 election, as well as other crimes. He has pleaded not guilty in the case.

Gates pleaded guilty in 2018 to lying to the FBI and to conspiracy. He testified later that same year against his former boss and onetime Trump campaign chief Manafort, who is now serving a 7½-year prison term for multiple crimes. Gates has yet to be sentenced for his crimes.