US Democrats have vowed to find new ways to pressure President George W Bush over his handling of the Iraq war.
The promise came after they failed to break a Senate deadlock to hold a debate on Mr Bush’s unpopular strategy.
Democrats regrouped from yesterday's setback by floating new strategies to challenge the president's plan to introduce a 'surge' of some 21,500 forces into Iraq.
Top among the options under consideration by Democratic lawmakers is a proposed measure that would revoke the October 2002 authorisation that allowed Bush to invade Iraq.
Separately, 60 people have been killed and 131 others injured in two car bombs in a Shia district of the Iraqi capital, Baghdad.
The explosions in an open-air market region in New Baghdad, in the east of the city, came as Iraq began to re-open border crossings with Iran and Syria.
The crossings were closed for three days as part of a crackdown on the ongoing violence.
Baghdad's markets have been hit by a spate of particularly deadly car bombings since the start of the year.
Some 71 people were killed a week ago in Shorja wholesale market, prompting US generals to look at pedestrianising the bigger markets.
Also today, a third car bomb killed two people when it exploded near a police checkpoint in Sadr City, a stronghold of radical Shia cleric Moqtada al-Sadr's Mehdi Army.
Earlier, police had reported finding just five bodies shot, tortured and dumped in Baghdad yesterday, a dramatic drop from the 40-50 they typically report each day.
It was one of the lowest tolls since the bombing of a Shia shrine in Samarra a year ago unleashed a wave of sectarian violence that has killed tens of thousands of people.