Thousands of American troops have gathered on the outskirts of the city following a spate of attacks by rebels which left 60 people dead.

The troops used night vision to seize the bridges, which are the main routes out of the west of the city.

As dawn broke, coalition forces were coming under heavy fire from rebels.

US planes have been battering what they call rebel positions for the past few weeks in a bid to make entry into the city easier.

Emergency

On Sunday, the Iraqi prime minister Iyad Allawi declared a 60-day state of emergency across the country.