The US Senate has approved a largely symbolic resolution urging an end to President Donald Trump’s military conflict with Iran, marking a fresh challenge to the White House as it seeks a long-term diplomatic agreement with Tehran.
The measure, which had already passed the House of Representatives, was approved by the Senate in a 50-48 vote. It directs the president to withdraw US forces from hostilities involving Iran unless Congress formally authorizes military action.
Although the resolution does not require Trump’s signature and has uncertain legal effect, its passage places both chambers of Congress on record against the conflict that erupted following US and Israeli strikes on Iran in late February. The fighting disrupted global energy markets and expanded into a wider regional confrontation involving Lebanon and several Gulf states.
Trump dismissed the vote on his Truth Social platform, describing it as poorly timed and insignificant. He argued that lawmakers were making his job more difficult but insisted he would achieve his objectives regardless.
The vote comes as the administration pursues a 60-day diplomatic effort aimed at transforming a preliminary agreement with Iran into a comprehensive deal covering Tehran’s nuclear programme, sanctions relief and the future of the Strait of Hormuz.
Senate Democratic leader Chuck Schumer pushed for the vote after several Republican lawmakers expressed concerns about both the conflict and the administration’s approach to ending it. Schumer argued that Republicans needed to publicly demonstrate their position rather than voice concerns privately.
The resolution previously passed the Republican-controlled House with support from all Democrats and four Republicans, representing a rare break from Trump on issues of war and national security. Democrats maintain that the president violated constitutional requirements by initiating military action without congressional approval.
Under the 1973 War Powers Act, presidents are generally required to obtain congressional authorization within 60 days of committing US forces to hostilities, although administrations from both major parties have often disputed the law’s interpretation and scope.
The White House has argued that efforts to limit the president’s authority in relation to Iran are unconstitutional. Officials also maintain that the conflict effectively ended following an April ceasefire announced by Trump and warn that congressional restrictions could undermine US leverage during ongoing negotiations.
House Speaker Mike Johnson previously argued that constraining the commander-in-chief during sensitive diplomatic talks could be risky.
However, critics from both parties contend that military operations continued beyond the legal deadline and point to Trump’s repeated warnings of possible renewed strikes. Many lawmakers are also concerned about the economic consequences of the conflict, including higher energy prices, disrupted trade routes and increased pressure on American households already dealing with inflation ahead of the midterm elections.
Negotiations between Washington and Tehran have accelerated since Trump and Iranian President Masoud Pezeshkian reached a preliminary agreement designed to reduce regional tensions and reopen the Strait of Hormuz. Nevertheless, major disagreements remain unresolved.
Iran announced on Tuesday that inspectors from the International Atomic Energy Agency would not be permitted to inspect nuclear facilities previously targeted by US and Israeli strikes. The statement contradicted claims by Vice President JD Vance that Tehran had agreed to restore full inspections.
Trump later asserted on social media that Iran had accepted the highest level of nuclear monitoring. Meanwhile, Iranian official Mohammad Bagher Ghalibaf stated that the Strait of Hormuz would not return to pre-war conditions, despite efforts to maintain communication channels and keep the strategic waterway open.
