WASHINGTON -- One day after loudly and publicly vowing to defy a subpoena, a former Trump campaign aide spent Tuesday digging through his email and compiling documents requested by special counsel Robert Mueller.

Sam Nunberg said he'd been working since 6 a.m. to produce the thousands of emails and other communications with and about 10 ex-campaign officials.

"I thought it was a teachable moment," he said of his 24 hours in the limelight. He also said he planned to appear Friday before a grand jury, as Mueller had requested.

Nunberg had earlier balked at complying with the subpoena, spending Monday lashing out at President Donald Trump and his campaign and threatening to defy Mueller in a series of interviews.

"Why do I have to do it?" Nunberg told CNN of the subpoena. "I'm not co-operating," he said later as he challenged officials to charge him. But in an interview Monday night with The Associated Press, Nunberg reversed himself, and predicted that, in the end, he'd comply.

"I'm going to end up co-operating with them," he said.

Trump was not pleased to see his former aide, with whom he has had an up-and-down relationship, go on an interview binge, a person familiar with the president's views said Tuesday. The person was not authorized to discuss private conversations publicly.

In his interviews, Nunberg said Mueller may already have incriminating evidence on Trump directly, although he would not say what that evidence might be.

But Trump was also somewhat amused by the media spectacle Nunberg created, the person said.

A spokesman for the special counsel's office declined to comment.

In his interviews with the AP, Nunberg cast Mueller's subpoena demands as unreasonable. He said he'd traded numerous emails a day with Roger Stone, a Trump adviser, and former White House chief strategist Steve Bannon, and said he didn't have 80 hours to spend digging through his files.

"I am 36 years old. I'm trying to build a business. I have clients. I have deadlines I can't make because of this stuff. What am I supposed to do?" he said of his situation. He said his lawyer thought his performance "was somewhat entertaining" and told Nunberg he knew he was "going to comply the whole time."

He also insisted that he was sober during the interviews. CNN's Erin Burnett had told Nunberg on air that she smelled alcohol on his breath.

Stone told MSNBC that Nunberg "marches to his own drummer" and was not speaking at Stone's behest.

"I would urge Sam Nunberg to co-operate," he said.

Nunberg was the first witness in the ongoing federal Russia investigation to openly threaten to defy a subpoena. But he was not the first to challenge Mueller: Former Trump campaign chairman Paul Manafort filed a lawsuit in January challenging Mueller's authority to indict him.

Associated Press writer Jonathan Lemire in New York contributed to this report.