The US Senate has approved a war powers resolution directing President Donald Trump to halt US military action against Iran, marking a rare bipartisan challenge to the administration's military policy.

The measure passed by a 50-48 vote, with a small number of Republicans joining Democrats in support. Although the resolution is largely symbolic and does not require Trump's signature, it reflects growing concern in Congress over continued US involvement in the conflict.

The White House has argued that the resolution is unconstitutional and not legally binding, while legal experts suggest any enforcement could ultimately be decided by the courts.