Democrats slammed Republicans as “cowards” for delaying the voting procedure into next month, while Republicans argue the move was to allow lawmakers unable to attend the vote a chance to cast their say.

The measure marks a symbolic win for Democrats and a growing number of Republicans who have questioned the Trump administration's war with Iran.

The Senate voted 50-47 to advance a resolution limiting President Trump's Iran war powers, with four Republicans breaking ranks to join Democrats in a significant bipartisan move.