President Donald Trump will have to override his advisers if he wants to make good on a campaign promise to abandon the Iran nuclear agreement, according to former U.S. Ambassador to the United Nations John Bolton, who published a draft proposal for exiting the accord on Monday.

Bolton alluded to a rift within the administration over whether the United States should scrap the landmark deal, and said he was recently denied a meeting with Trump on the issue after staff changes at the White House.

“It’s a question of who prevails here: the president or his advisers,” Bolton told the Washington Free Beacon on Tuesday. “Based on what’s been reported in the press, I think [Trump] does believe this deal is detrimental to American interests, so if he wants to get out of it I’m providing a way to do it.”

Bolton, once considered for secretary of state and national security adviser during the presidential transition, said in an op-ed published Monday in National Review he was asked last month by Trump’s now-ousted strategist, Steve Bannon, to draft a policy proposal on how the United States could withdraw from the nuclear accord.