A rare bipartisan coalition in the US House of Representatives has approved a resolution seeking to prevent President Donald Trump from expanding military operations against Iran, highlighting growing unease in Washington over the escalating conflict and the administration’s use of presidential war powers.
The measure passed by a narrow 215-208 margin, with four Republican lawmakers joining Democrats in backing the proposal. The vote marks the strongest congressional challenge so far to Trump's handling of the war, which began in February.
The resolution now moves to the Republican-controlled Senate, where its prospects remain uncertain. Even if approved by the Senate, the measure would still face a likely presidential veto, requiring a two-thirds majority in both chambers to override.
The House action represents the fourth attempt by lawmakers to restrict Trump's authority to conduct military operations against Iran without explicit congressional approval.
A similar proposal cleared a procedural hurdle in the Senate in May after several previous failures but has yet to receive a full Senate vote.
The vote exposed fresh divisions within the Republican Party, with four representatives breaking ranks to support the measure. Their support added to growing signs of dissent within Republican circles over the administration's foreign policy and military strategy. The vote came only days after conservative lawmakers forced the White House to retreat from plans for a $1.8 billion political initiative.
Supporters of the resolution argue that Congress alone has the constitutional authority to declare war and that continued military operations against Iran require legislative approval.
Democrats described the vote as a significant step towards reasserting congressional oversight of military action and limiting the risk of a prolonged conflict in the Middle East.
Critics of the war contend that the campaign has failed to achieve its stated objectives while contributing to higher energy prices and complicating diplomatic efforts surrounding Iran's nuclear programme.
The congressional vote comes even as Washington and Tehran continue discussing a possible agreement to end hostilities.
Despite an existing ceasefire framework, military exchanges have continued in recent days. The US has carried out fresh strikes against Iranian targets, while Iran has responded with attacks that included strikes on Kuwait, a key US ally in the Gulf.