WASHINGTON — Former national security adviser John Bolton’s abrupt departure on Tuesday came after President Donald Trump suggested he might lift some U.S. sanctions on Iran as an incentive for Tehran to come to the negotiating table, according to a person close to Bolton.

This person said Trump raised the idea of lifting sanctions during a discussion with Bolton in the Oval Office on Monday afternoon. Bolton made clear to the president that he strongly disagreed with the idea, this person said.

Bolton was out as national security adviser the following morning, though he and Trump disagree over who made that decision. The president has said he fired him, while Bolton has said he resigned.

The White House did not immediately respond to a request for comment.

As national security adviser, Bolton was a leading advocate of the Trump administration’s so-called “maximum pressure campaign,” designed to squeeze Iran’s economy until its leadership was forced to curtail its aggression in the region and concede to U.S. demands to dismantle its nuclear program.

Trump withdrew the U.S. from the 2015 Iran nuclear deal last year. Iran has since decided not to comply with the agreement. Trump recently has said he would meet with Iranian President Hassan Rouhani, perhaps later this month on the sidelines of the United Nations General Assembly session in New York, without preconditions.

Iran has said it won’t negotiate with the U.S. until sanctions are lifted.

This was not the first time Trump has brought up the idea of easing sanctions to bring Iran to the negotiating table, according to a U.S. official familiar with the Iran policy discussions.

The president has “thrown out the idea before” because he believes if he gets Iranian officials to talk, he can make a deal. But the discussion on Monday was more than just a suggestion, the official said, as the president seemed to really be considering the idea ahead of a hoped-for meeting with the Iranians at the United Nations later this month.

French President Emmanuel Macron has proposed providing Iran with $15 billion in non-U.S. funds to jump-start talks. Trump has suggested he might sign off on such a proposal, which would require the U.S. to advise financial institutions that they would not face penalties if they facilitate such transactions.

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But the person close to Bolton said the president went further during a 2 p.m. meeting on Monday in suggesting he would lift U.S. sanctions. The possibility of Iran sanctions relief was in part what prompted Bolton to submit a resignation letter to the president the following morning, this person said.

Trump indicated on Wednesday that he might be open to sanctions relief.

“We’ll see what happens,” he told reporters when asked about possibly easing sanctions on Iran.