Senate Republicans have again blocked a war powers resolution intended to require President Donald Trump to seek congressional approval or end US military action against Iran. The vote reflects continued Republican backing for the president’s discretion in the conflict, despite concerns about dwindling munitions, rising petrol prices and the absence of clearly stated objectives.

The resolution was aimed at forcing an immediate halt to US involvement unless Congress authorised it, but Republican senators prevented it from advancing. The debate comes as the Pentagon seeks substantial additional funding for a potential Iran conflict, reportedly including an $80 billion request, while critics question the scale, cost and direction of the war.