Mr. Stone was asked by ABC News whether there was any chance he would cooperate at Mr. Mueller’s request. The special counsel is looking into whether Trump campaign officials aided Russia’s efforts to interfere in the 2016 U.S. election, which Mr. Trump and Moscow have denied.
“You know, that’s a question I would have to—I would have to determine after my attorneys have some discussion,” Mr. Stone said Sunday. “If there’s wrongdoing by other people in the campaign that I know about, which I know of none, but if there is, I would certainly testify honestly.”
Mr. Stone appeared combative toward federal prosecutors through most of the interview, calling the indictment against him last week “thin as piss on a rock” and accusing authorities of using “Gestapo tactics” in his arrest early Friday with what he said was a 29-member SWAT team that arrived at his Florida house in 17 vehicles.
“I will plead not guilty to these charges,” he said. “I will defeat them in court.”
A spokesman for the special counsel declined to comment Sunday.
A federal grand jury accused Mr. Stone of lying to Congress to cover up his efforts to obtain and share with Trump campaign officials plans by the website WikiLeaks to publish emails that were damaging to Hillary Clinton, Mr. Trump’s 2016 Democratic opponent. U.S. officials have said those emails were hacked by Russian intelligence officers.
In the seven-count indictment, Mr. Stone also was charged with obstructing the congressional inquiry and trying to persuade a witness to lie to a House committee.
Mr. Stone becomes the latest person to be ensnared in Mr. Mueller’s nearly two-year-old probe that is also looking into whether the president has obstructed justice. He was released on a $250,000 bond.
In the Sunday interview, Mr. Stone said the information about WikiLeaks that he purveyed to the Trump campaign was well-known to the public at the time. He denied lying to Congress, saying he had forgotten about some emails and text messages that he had sent.
“I am human and I did make some errors,” he said. “But they are errors that would be inconsequential in the scope of this investigation.”
In Thursday’s indictment, Mr. Mueller accused Mr. Stone of withholding information that was material to the House panel’s Russia investigation, including communications Mr. Stone had with conservative activist Jerome Corsi about WikiLeaks’ plans to release emails.
Mr. Corsi told The Wall Street Journal in November he had informed Mr. Stone that WikiLeaks had Clinton campaign chairman John Podesta’s emails in the summer of 2016. He also said he told the grand jury that he helped Mr. Stone create a “cover story” for a tweet in which Mr. Stone said it would soon be “Podesta’s time in the barrel.” Mr. Stone has denied the claim and has accused Mr. Corsi of lying.
In a Sunday interview with CNN, Mr. Corsi said he would be “happy to testify” about his communication with Mr. Stone. He also told the Journal Friday that everything in the indictment regarding himself—referred to as “Person 1” in the document—is accurate.
Another Stone associate mentioned in the indictment, New York radio personality Randy Credico, has also told the Journal he is willing to discuss his communication with Mr. Stone. Mr. Stone was accused of witness tampering in the indictment in part because of his correspondence with Mr. Credico.
In October 2017, Mr. Stone told House investigators that Mr. Credico was his intermediary to WikiLeaks. Then, when Mr. Credico was subpoenaed by panel, Mr. Stone urged Mr. Credico to “stonewall” the probe, according to messages listed in the indictment. “Plead the fifth. Anything to save the plan,” Mr. Stone texted his former friend.
Last year, when things grew tense between the two men, Mr. Stone used Mr. Credico’s decision to rely on the Fifth Amendment, which protects citizens against self-incrimination, against him.
When asked by the Journal if he had proof that Mr. Credico was his so-called backchannel to WikiLeaks in the summer of 2016, as Mr. Stone alleged, Mr. Stone responded in a text message: “I addressed these questions under oath before the house intelligence committee. Mr. credico asserted his fifth amendment rights and refused to be questioned. Who’s lying? Be certain to note that in your story.”
In his television interview Sunday, Mr. Stone said he was only joking when he encouraged Mr. Credico to plead the Fifth and that prosecutors had misrepresented what he called a “humorous exchange.”
Mr. Credico, indicating a change of heart last week, told the Journal he would be willing to appear before both House and Senate committees if he is subpoenaed again.
— Sarah Chaney contributed to this article.
Write to Shelby Holliday at firstname.lastname@example.org and Alan Cullison at email@example.com
Appeared in the January 28, 2019, print edition as ‘Stone Willing to Help Mueller if He Is Asked.’