Fierce fighting broke out in the central Baghdad district of Haifa Street on Tuesday as US and Iraqi forces moved in against insurgents, in an area once viewed as a showcase for the ability to control Baghdad neighbourhoods, by “saturating” them with military forces.

The battles, in which US and Iraqi ground forces were supported by helicopters and fighter jets, reportedly left at least 50 insurgents dead, and came hours before George W. Bush, US president, was set to announce a plan for Iraq that is expected to feature a “surge” of as many as 20,000 new US troops.