WASHINGTON (AP) — The Senate tried and failed again Tuesday to advance a war powers resolution that would halt the U.S. military action against Iran, in what has become an almost weekly effort to rein in President Donald Trump as the administration floats a new plan to bring an end to the nearly four-month long war.

Senators of both parties have have been skeptical of the Trump administration's emerging Iran deal and frustrated by the White House's refusal to share details. They are expecting a briefing from the administration, but nothing has been scheduled before Friday's planned deadline for the two sides to sign the agreement.

The vote was 47-48, with four Republicans joining most Democrats in supporting the war powers resolution. That fell short of the majority needed to advance it.

“Join me in putting a check on this president’s lawless warmongering,” said Sen. Raphael Warnock, D-Ga., who proposed the resolution, in a speech before the voting.

“The time is always right to do what’s right,” he said.

The measure was the ninth time the senators have tried to advance a resolution to end the war that U.S. and Israel launched against Iran over the nation's nuclear program. Trump launched the war on his own, without congressional approval, but as it drags on lawmakers have grown concerned over the costs, strategy and end game.

Congress begins to exert influence over the war

The House for the first time approved its own war powers resolution to halt U.S. military action against Iran this month, when a small number of Republicans crossed over to join with the Democrats to pass the measure.

Meanwhile, the Senate has settled into a familiar pattern, one vote short of the tally that would be needed to pass the measure, if all senators are present and voting.

Republicans Lisa Murkowski of Alaska, Susan Collins of Maine, Rand Paul of Kentucky and Bill Cassidy of Louisiana voted in favor of the war powers resolution. Democratic Sen. John Fetterman of Pennsylvania voted against.

Cassidy broke ranks with his party last month, voting for the first time to end the military action against Iran after having lost his own primary reelection bid in Louisiana. Trump had endorsed his challenger.

One Republican to watch, retiring Sen. Thom Tillis of North Carolina, said he supports Trump's actions in Iran, even as he is closely watching the details of the administration's Iran deal.

“I just don’t think that it’s productive for me to cast a protest vote on something that I fundamentally support.” Tillis said. "I support the engagement in Iran. But I have a discerning eye over what the agreement will say.”

More votes ahead on Iran war

Democratic Sen. Tim Kaine of Virginia has been leading the party's efforts to halt the war in Iran unless Congress has authorized it. He vowed to keep pushing the measures forward on an almost weekly basis.

Kaine has argued that as negotiations are underway to end the conflict, Congress must work to ensure the U.S. does not resume military strikes in what has been a fragile ceasefire.

“If we're really in a period of maybe some stability here, let's not just allow it to start up again without Congress being involved in that decision,” Kaine said.

“If there are deals on the table, I don't know that we want the president to be the sole determinant of whether a deal's a good thing," he said. “He may decide, well that's not a good enough deal, let's go back to war. Well, hold on a second. We might want to weigh in on that.”

Senators are also beginning to discuss what Congress will do, if anything, to provide oversight of Trump's emerging Iran deal. Some senators have said the Senate must vote on any agreement the Trump administration strikes with Iran over its nuclear program. Others have said a vote in Congress is not necessary.

Congress in 2015 approved the Iran Nuclear Agreement Review Act, which spells out out requirements for the administration to submit any deal involving Iran's nuclear program for review by Congress.

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Associated Press writer Mary Clare Jalonick contributed to this report.

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