US Senate joins House in rebuke of Trump over his war in Iran

Alaska Sen. Lisa Murkowski was among four Republicans who joined Democrats to vote for the measure

The U.S. Capitol on April 9, 2026. (Ashley Murray/States Newsroom)

By Ashley Murray

Stateline

The Republican-led U.S. Senate served up a rare public check on President Donald Trump’s agenda Tuesday when it voted to approve a House-passed War Powers Resolution to end hostilities in Iran.

Senate approval marked the first time both chambers have agreed in a rebuke of Trump over his war in Iran.

The concurrent resolution, which passed 50-48, does not require the president’s signature and its enforceability has been a perennial topic of debate. 

The Senate’s approval occurred against the backdrop of the administration’s peace deal negotiations with Iran, which have been criticized from both sides of the aisle.

Four Republicans joined Democrats in voting for the measure: Lisa Murkowski of Alaska; Rand Paul of Kentucky; Louisiana’s Bill Cassidy, who recently lost his primary race after Trump endorsed an opponent; and Susan Collins, who’s fighting a tough reelection campaign in Maine. 

Democrat John Fetterman of Pennsylvania voted no. Paul and Fetterman have broken ranks with their parties on several previous Iran War Powers Resolution votes.

Republican Sens. Mitch McConnell of Kentucky, who was recently hospitalized, and Dave McCormick of Pennsylvania did not vote. McCormick was with Trump on a trip to Pennsylvania.

Debate over impact

Trump administration officials, including Secretary of State Marco Rubio, argue that War Powers Resolutions are not constitutional. 

The U.S. Supreme Court in 1983 ruled against the validity of congressional measures that do not require a president’s signature.

Senate Minority Leader Chuck Schumer, D-N.Y., said Congress “stood up to Donald Trump and voted to end his costly, unnecessary, and devastating war with Iran.”

“Let me be clear: for the first time, this resolution has passed both chambers of Congress and does not require the President’s signature. The message from the only branch of government with the power to declare war is unmistakable: the Trump administration must withdraw U.S. forces from hostilities in Iran. The pressure on Republicans mounts,” Schumer said in a statement following the vote.

Rep. Gregory Meeks, D-N.Y., who sponsored the original resolution that passed the House on June 3, said the measure is binding and the president “must cease all hostilities against Iran.”

“Regardless of what President Trump says, this measure is binding under the War Powers Resolution, and I will explore all legal avenues to ensure the Executive complies with the will of Congress. Congress never authorized this failed war, and the president certainly has no authority to continue it indefinitely without our consent as the Constitution demands,” Meeks, the top Democrat on the House Committee on Foreign Affairs, said in a statement.

The White House declined to comment on the vote.

Negotiations continue

Administration officials, who maintain hostilities ended in early April, are on a 60-day clock to hammer out a final agreement with Iran. 

As part of a temporary memorandum of understanding in effect during talks, the administration lifted its naval blockade of Iranian ports and economic sanctions on Iranian oil, allowing the Islamic Republic to now sell on the global market. 

The interim deal also charges Iran with demining the Strait of Hormuz and allowing tankers and cargo ships to travel unimpeded while Iran and Oman create a scheme for passage through the narrow shipping route where one-fifth of the world’s petroleum traveled prior to the war.

Trump issued social media threats to Iran over the weekend as Iran’s new Persian Gulf Strait Authority continued to impose certain requirements for ships to pass.

Thirteen American service members died in the war launched by the U.S. and Israel on Feb. 28, and over 400 have been injured, according to the Pentagon. Thousands of civilians across Iran and the Gulf region were killed during the fighting.

• Stateline is part of States Newsroom, the nation’s largest state-focused nonprofit news organization.