Former ambassador John Bolton on Monday blamed Defense Secretary Jim Mattis and Secretary of State Rex Tillerson for their public spat with President Trump over Iran, and said members of Trump’s Cabinet need to keep personal views to themselves.

“I think it’s unfortunate overall, frankly, to have your top national security Cabinet members and advisers speaking in public about what their personal views are on highly important and very grave matters of foreign and defense policy,” he said on Fox News Monday.

Bolton was asked about Mattis and Tillerson, who have publicly opposed Trump’s pending decision to decertify the Iran nuclear deal, a move he is expected to announce this week.

“I just don’t think that these kinds of debates are to be held in public,” he said. “I think you hold them in the sit[uation] room, in a national security council meeting, or in the oval office.”

“It’s a privilege to work for a president in that capacity, and part of that privilege is, you give him your absolutely candid, unvarnished advice, he makes the decision, and then you toe the line, and when the time comes that you can’t toe the line anymore, you resign,” he said. “That’s the honorable thing to do.”

Bolton’s comments put him in line with Sen. Tom Cotton, R-Ark., who also said Trump’s staff should resign if they disagree with Trump’s moves.

Bolton also stressed that Trump’s decision to announce that Iran is not abiding by the deal does not have to mean he is pulling out of the deal.

“He may decertify under the Corker-Cardin legislation, but stay in the deal,” Bolton said. “And in fact, according to some press reports, [he] will ask Congress not to reimpose nuclear-related sanctions.”

Bolton predicted that this move would be a recipe for keeping the deal in place, and keeping U.S. nuclear sanctions against Iran shut off.

“You give this hot-potato to Congress now, in the middle of an effort to give tax cuts and tax reform, Congress will do nothing,” he said. “Which means, the default position is the Iran nuclear deal continues, the sanctions continue to be waived, and Iran continues to make progress toward deliverable nuclear weapons.”

“That’s why I have been saying the president’s got to get out of this deal, he’s got to cut and cut cleanly, and make it clear to the world this deal is not only not in America’s national interest, we will not abide by it any longer,” he said.