LONDON — British troops will not be pulled out of Iraq as planned, due to a recent surge of violence there, defense officials said today.

Defense Secretary Des Brown will inform lawmakers in the House of Commons on Tuesday that the scheduled withdrawal of some 1,500 British troops was on hold, officials said.

Prime Minister Gordon Brown said late last year that the number of British forces would be reduced to 2,500 starting in the spring, if commanders approve the plan.

Britain has about 4,000 troops stationed at an air base on the fringe of the southern Iraqi city of Basra. Forces withdrew from the city center late last year and have since focused only on training Iraqi troops and police.

But a surge in violence that has swept Baghdad, Basra and other Shiite areas has forced British troops back into a combat role, and has led British military chiefs to reconsider the pullout.

Violence erupted after Iraqi Prime Minister Nouri al-Maliki launched a crackdown against Shiite militias in Basra. Street battles have left more than 200 dead, including civilians, Iraqi troops and militants.

Followers of radical Shiite cleric Muqtada al-Sadr have been fighting Iraqi and coalition forces in the southern city — Iraq's commercial and oil hub — since Tuesday.

American forces have launched airstrikes in Basra, and the British army joined in the fighting for the first time Saturday, firing artillery to support an operation by Iraqi soldiers, military officials said.

Brown spokesman Michael Ellam said the British leader had always said decisions on troops withdrawal depend on the security situation in Basra.