Iran live updates: Senate narrowly votes to advance war powers resolution

The Senate narrowly advanced an Iran war powers resolution Tuesday by a vote of 50-47 -- marking the first time the Senate has approved moving forward with this resolution after seven previously failed votes.

Republican Sen. Bill Cassidy, who lost his primary in Louisiana over the weekend after President Donald Trump endorsed his opponent, voted yes to advance the resolution for the first time. He has not yet issued a statement explaining his change in position on the measure.

His GOP colleagues Sens. Rand Paul, Susan Collins, and Lisa Murkowski also voted for the resolution, along with the majority of Democrats. There were multiple GOP absences.

As in past votes, Democratic Sen. John Fetterman was the only Democrat to vote against the resolution.

The resolution "directs the President to remove U.S. Armed Forces from hostilities within or against Iran unless a declaration of war or authorization to use military force for such purpose has been enacted."

The resolution only needed a simple majority in the procedural vote to advance. The Senate would need to vote again to advance the bill. Right now, if no other member changes their votes and there is full GOP attendance, the measure would still ultimately fail. Though it's a breakthrough moment for Democrats who have for months been bringing war powers resolutions to the floor.

"It sort of feels like the momentum is slowly, not fast enough for me, but moving our way, and that's really positive," Sen. Tim Kaine, who has been leading the Democratic effort on war powers, told reporters after the vote.

-ABC News' Allison Pecorin and Lalee Ibssa

Asked if he personally believes the U.S. will reach a deal with Iran, Vice President JD Vance stopped short of confirming the two sides will agree.

"What I think is that the Iranians want to make a deal. What I think is that the Iranians recognize that a nuclear weapon is the red line for the United States of America, that they've internalized that. But we're not going to know until we're actually putting pen to paper on signing a deal," Vance told reporters during remarks at the White House Tuesday.

"We've had a lot of drafts, a lot of, you know, a lot of pieces of paper going back and forth. But I will not say with confidence that we're going to reach a deal until we're actually signing a negotiated settlement here," Vance said.

President Donald Trump offered an account of the details and timeline related to his decision to call off a planned attack on Iran this week, while setting a new deadline of next week for Iran to strike a deal or face strikes.

During an event showing the construction of the White House ballroom project on Tuesday, the president appeared to suggest that he had been “one hour away” from definitively ordering strikes Iran on Monday before he made the decision to delay the attacks at the request of allies in the region who said there has been progress with Iran peace talks.

"I was an hour away,” Trump said on Tuesday. “You're talking about yesterday? We were going to be striking very ... it would have been happening right now. Yeah, it was all done. The boats, the ships are all loaded. They're loaded to the brim, and we're all set to start,” Trump said.

But, the president said just moments later that he was “one hour away" from “making the decision” to carry out those strikes.

-ABC News' Michelle Stoddart and Isabella Murray

President Donald Trump said he was "an hour away" from striking Iran, saying the U.S. would have been striking "right now."

The ships are all "loaded" and ready to attack, Trump said during an event the White House Tuesday.