British Prime Minister Gordon Brown said Tuesday he won't revive plans to withdraw hundreds of troops from southern Iraq until local security forces win the battle to drive out militia groups. Brown said a plan to reduce troop numbers from around 4,000 to 2,500 would remain on hold. He has delayed the troop drawdown, which had been due to begin within weeks, following a recent spike in violence from militias in the oil-rich southern city of Basra. Street battles erupted last month after Iraqi Prime Minister Nouri al-Maliki launched a crackdown against Shi'te militias aided by artillery and air support provided by US and British forces. But the offensive stalled amid resistance from militiamen. Around 1,000 Iraqi security troops refused to fight or join the militias, instead handing them weapons and vehicles.