Appearing Thursday on CNBC with Hadley Gamble, former Secretary of State John Kerry denied conducting back-channel meetings with the Iranian government after President Donald Trump accused the Obama-era official of violating the Logan Act by discussing the U.S.-Iran nuclear agreement.

A partial transcript is as follows:

HADLEY GAMBLE: A couple of weeks ago I sat down with Secretary of State Mike Pompeo and I asked him if he was concerned by the fact that the Iranian felt more comfortable dealing with you, given your long history of dealing with them, than perhaps they did with the U.S. government. And he said any cooperation or any communication between a former secretary of state and the Iranian regime is “inappropriate.” Could you respond to that?

JOHN KERRY: Well, I haven’t talked to the Iranians substantively about any issue. I’ve only talked with one Iranian once between the decision that was made to pull out. I saw the foreign minister briefly for a few minutes at the Munich Security Conference. But I have not said a word, substantively, to what they ought to do or not do, publically like this, since the decision was made to pull out of the Iran nuclear deal. From that forward, this is a public issue, and I don’t engage in any diplomacy.

GAMBLE: You haven’t had any back-channeling?

KERRY: No, I haven’t had any back-channel on that issue since the decision was made to move out. And before that, it was not a back-channel. I met publicly, as the New York Times editorial board did, as members of Congress did, as senators did and as other secretaries of state have done throughout history.