Monday on CNN’s “The Lead,” former Trump aide Sam Nunberg called in to say that he will refuse to comply with the subpoena by special counsel Robert Mueller to appear in front of a federal grand jury.

During his wide-ranging interview, Nunberg told host Jake Tapper that he thought Mueller may have “something” on Trump.

Partial transcript as follows:

NUNBERG: I’m not cooperating. Arrest me.

TAPPER: You’re not cooperating, arrest you?

NUNBERG: Yes. You’re going to arrest me, arrest me. Do you know what? I’m not a fan of Donald Trump, Jake.

TAPPER: I know, you had a big falling out.

NUNBERG: I’m not a fan of his. When they start asking for stuff like this, Trump is right. It is a witch hunt.

TAPPER: When you did meet with the members of the special prosecutor’s team and you said they acted very professionally?

NUNBERG: They acted professionally and I was very impressed.

TAPPER: You were very impressed. What were they asking you about?

NUNBERG: They asked about everything in terms of my relationship with Trump, in terms of my — they even — you know, my father worked for Trump in the 1980s, if you read ‘Art of the Deal’ Trump mentions it. They asked about stuff like that. You wouldn’t believe it. And they know—they know something on him. And Jake, I don’t know what it is. Perhaps I’m wrong, but he did something.

TAPPER: You think that they have him on something but you don’t know if it is related to if Russians or something else.

NUNBERG: I think it, I think if they have him on something, they’re smart enough to know, if they have him on something, it has to be during election. Because the same way that they went after Bill Clinton when he was governor of Arkansas, and they were right to, they have to go, the minute Trump is a politician, they can go after him. Now, Sarah Huckabee has attacked me again and I’ll be more than happy to deal with her face to face. I would be more than happy to go back to court with her. I think she’s terrible, by the way.