The Trump administration seemed unlikely Tuesday to accept Iran's offer to end the war and reopen the Strait of Hormuz if the U.S. lifts its blockade on the country.

The proposal would postpone discussions on the Islamic Republic’s nuclear program, something that U.S. Secretary of State Marco Rubio appeared to rule out in a Fox News interview Monday.

“We have to ensure that any deal that is made, any agreement that is made, is one that definitively prevents them from sprinting towards a nuclear weapon at any point,” he said of the proposal, which was delivered to the U.S. by Pakistan.

The White House said U.S. President Donald Trump's national security team discussed the offer and Trump would address it later.

The offer emerged Monday as Iran Foreign Minister Abbas Araghchi visited Russia, which has long been a key backer of Tehran. It was unclear what, if any, assistance Moscow might offer now.

Since the war began, at least 3,375 people have been killed in Iran and at least 2,521 people in Lebanon, where fighting between Israel and the Iran-backed Hezbollah militant group resumed two days after the Iran war started. Another 23 people have been killed in Israel and more than a dozen in Gulf Arab states. Sixteen Israeli soldiers in Lebanon, 13 U.S. service members in the region and six U.N. peacekeepers in southern Lebanon have been killed.

Here is the latest:

U.S. Secretary of State Marco Rubio was asked in a Fox News interview about Iran’s latest proposal, which would postpone discussions on its nuclear program but end its chokehold on the Strait of Hormuz if the U.S. lifts its blockade and ends the war.

“There’s no doubt in my mind that at some point in the future if this radical clerical regime remains in charge in Iran, they will decide they want a nuclear weapon,” Rubio said.

“That fundamental issue still has to be confronted,” he said. “That still remains the core issue here.”

Asked if he thinks the Iranians are serious about a deal, Rubio said they are skilled negotiators looking to buy time.

“We can’t let them get away with it,” Rubio said. “We have to ensure that any deal that is made, any agreement that is made, is one that definitively prevents them from sprinting towards a nuclear weapon at any point.”