Iranian President Hassan Rouhani threw cold water Tuesday on President Trump’s suggestion that the two could meet to try to end a nuclear standoff — saying the US must “take the first step” by lifting sanctions imposed on Tehran.

Trump said Monday during the G-7 summit in France that he was ready to meet with the Iranian leader within weeks should the Muslim theocracy change its behavior.

The president’s overture followed a surprise intervention by French President Emmanuel Macron at the summit to try to bring Washington and Tehran together after decades of conflict.

“Without the US’s withdrawal from sanctions, we will not witness any positive development,” Rouhani said during a televised speech Tuesday, adding that Washington “holds the key” to what happens next.

“If someone intends to make it as just a photo op with Rouhani, that is not possible,” he said, adding that Iran had already ruled out ever doing what worries Washington the most — building an atomic bomb.

“If honestly this is your only concern, this concern has already been removed” through a fatwa issued by supreme leader Ayatollah Ali Khamenei, Rouhani said.

“We don’t (intend to) make an atomic bomb … our military doctrine is based on conventional arms,” he added.

Khamenei issued a fatwa — a religious decree — against nuclear weapons in 2003 and has reiterated it several times since.

Foreign Minister Mohammad Javad Zarif — who made a surprise trip to Biarritz for talks on the sidelines of the summit — said the prospects for a meeting between Trump and Rouhani were “unimaginable” without the US rejoining the 2015 nuclear deal with Tehran.

Speaking at the summit, Trump ruled out lifting economic sanctions to compensate for losses suffered by Iran, which has scaled back its commitments under the pact in retaliation for the US sanctions.

“We will continue to scale back our commitments under the 2015 deal if our interests are not guaranteed,” Rouhani said in his speech Tuesday. “Tehran has never wanted nuclear weapons.”

Before his U-turn, Rouhani on Monday expressed readiness to negotiate a way out of the crisis, which has deepened after Trump unilaterally pulled the US out of the accord last year.

Under the deal, Iran agreed to limit its enrichment of uranium in exchange for the lifting of economic sanctions.

“If I knew that going to a meeting and visiting a person would help my country’s development and resolve the problems of the people, I would not miss it,” he said.

“Even if the odds of success are not 90 percent but are 20 percent or 10 percent, we must move ahead with it. We should not miss opportunities.”

Since the US pullout from the nuclear accord, Iran has lost billions of dollars in business deals as Washington reimposed and escalated sanctions largely blocking Tehran from selling crude abroad, a crucial source of revenue for the Islamic Republic.

Trump and Rouhani are both due to attend the UN General Assembly in September.

With Post wires