President Donald Trump sharply criticized Senate Republicans during a Wednesday visit to the Capitol for allowing a vote that sought to limit his authority to conduct military operations in Iran, intensifying tensions within the GOP and disrupting the Senate’s agenda ahead of the 2026 election cycle.

Trump was invited to speak at a Republican luncheon organized by Senator Rick Scott of Florida, where he had initially planned to advocate for a proof-of-citizenship voting bill. However, the discussion instead centered on the Senate’s vote the previous day to approve a war powers resolution addressing the ongoing conflict in Iran. The measure, largely symbolic, would allow Congress to formally rebuke the administration’s military actions; a similar resolution had already been passed by the House earlier in the month.

Four Republican senators—Lisa Murkowski of Alaska, Susan Collins of Maine, Rand Paul of Kentucky, and Bill Cassidy of Louisiana—joined Democrats to support the resolution. In response, Trump called these senators “losers” on social media and criticized them directly during the closed-door meeting.

While most Republicans remained silent, Senator Bill Cassidy—who was defeated in his primary last year after Trump endorsed his challenger—publicly defended his vote. Cassidy stated that he confronted the president during the meeting, asserting that the administration had not adequately informed the American public about the conflict, which was originally expected to last only a few weeks but has extended to four months. He said the exchange became heated, with both men raising their voices before efforts were made to calm the situation.

Cassidy further explained his stance, saying he would continue to support the war powers resolution until he received a formal briefing on the matter. According to an individual familiar with the private session, Trump repeatedly told Cassidy to sit down and at one point called him a “lunatic,” though the president later described the meeting as “really great” in public remarks while acknowledging there were a few people he did not favor.

This confrontation is the latest in a series of disputes between Trump and Senate Republicans, which have complicated legislative negotiations and sidelined efforts to advance other key priorities, including a recently passed housing bill. The president canceled a planned signing ceremony for that bill, which had bipartisan support, signaling his unwillingness to compromise in the current climate.

The discord following the Iran war powers vote reflects broader fissures within the Republican caucus as Trump seeks to assert his influence over the party ahead of upcoming elections, raising questions about the Senate’s ability to unite on major policy issues amid ongoing internal divisions.