The US House of Representatives is set to vote on a resolution that aims to limit President Donald Trump’s ability to make war on Iran.
The largely symbolic measure seeks to mandate congressional approval for any conflict with Iran, except in cases of an imminent attack against the US.
It is expected to pass the Democratic-held House, but faces tougher prospects in the Republican-controlled Senate.
Neither the US nor Iran have declared plans for further military action.
Iran this week fired missiles at Iraqi bases housing American forces, injuring no-one, after the US last week killed a senior Iranian commander in a Baghdad drone strike.
Thursday’s measure directs the president to “terminate the use of United States Armed Forces” against Iran unless granted congressional authorisation.
It offers an exception when necessary to “defend against an imminent armed attack”.
Even if the measure clears Congress, it would not reach the president’s desk for a potential veto because it is known as a concurrent resolution, which lacks the force of law.