Trump says we're 'blowing up the whole country' if Iran doesn't make deal in 48 hours

Secretary of State Marco Rubio continued to make the case for the U.S. war with Iran as Americans prepare to hear from President Donald Trump in a primetime address to the nation on Wednesday night.

“Many Americans are asking, 'Why did the United States have to attack Iran now?'" Rubio said in a video posted by the White House on Tuesday. "Well, let me explain. Iran wants to have nuclear weapons. Of that, there is zero doubt."

Rubio said Iran was "trying to build a conventional shield, in essence have so many missiles, have so many drones that no one could attack them and they were well on their way."

He added, "We were on the verge of an Iran that had so many missiles and so many drones, that no one could do anything about their nuclear weapons program in the future. That was an intolerable risk."

Regarding the U.S. decision to launch strikes on Feb. 28, Rubio said: "This was our last best chance to eliminate that conventional threat -- that conventional shield that they were trying to build -- and the president made the right decision to wipe it out now. That is the goal of this operation."

-ABC News' Nicholas Kerr

President Donald Trump will address the nation with "an important update on Iran" at 9 p.m. ET Wednesday, according to White House press secretary Karoline Leavitt.

President Donald Trump said on Tuesday that Iran doesn't need to make a deal with the U.S. as a prerequisite to stopping the ongoing U.S. military operation.

"Iran doesn't have to make a deal, no," he told reporters during an executive order signing about elections in the Oval Office. "I've spoken to a lot of people. It's a new regime. They are much more accessible."

"When we feel that they are for a long period of time put into the stone ages and they won't be able to come up with a nuclear weapon, then we'll leave," he said. "Whether we have a deal or not, it's irrelevant."

Pressed on his timeline for ending the war, Trump speculated that it could be "two or three weeks."

The president also again seemed to indicate that the Strait of Hormuz will be left for other nations to handle after the U.S. leaves.

"If France or some other country wants to get oil or gas, they'll go up through the Strait and -- Hormuz Strait -- they'll go right up there and they'll be able to fend for themselves. I think it would be very safe, actually, but we have nothing to do with that," Trump said.

-ABC News' Meghan Mistry, Nicholas Kerr and Michelle Stoddart

One suspect involved in the abduction of American journalist Shelly Kittleson was arrested on Tuesday, the Interior Ministry of Iraq confirmed Tuesday, adding that efforts to locate her continue.

In another statement the ministry shared details of their pursuit which resulted in the seizure of a car belonging to the kidnappers.

A car overturned while kidnappers were trying to escape and the security forces arrested one of the suspects, according to the ministry.

-ABC News' Somayeh Malekian, Bader Katy and Ghazi Balkiz