KANDAHAR (Agencies) - Taliban fighters have pledged to defend the town of Marjah from an imminent Nato offensive, saying that their ranks had been bolstered by foreign fighters eager to fight against western troops. NATO commanders called on the Taliban to surrender as troops dug in Monday for a major assault on one of the last insurgent strongholds in southern Afghanistan, sending thousands of residents fleeing.The Taliban remained defiant as civilians of the Marjah plain accused the militia, which is leading an eight-year insurgency, of massing fighters and arms for a bloody battle in Helmand province expected to start this week. Taliban fighters prefer to stay and fight, Yousuf Ahmadi, a purported Taliban spokesman, told AFP by telephone from an undisclosed location. Afghan and foreign forces have come to the Marjah area and our mujahedeen forces are also in the area firing rockets at them, he said. Mullah Sharadulldine, a Taliban officer who says he commands 145 men, said fighters had been bolstering their defences of the town, believed to include mines and booby traps hidden in surrounding irrigation ditches. An estimated 1,000 or more Taliban fighters were believed to be in the town. We are well prepared to fight any kind of attacks by the infidels, he told the Financial Times by telephone. We also have brave international Mujahideen beside us and we have also expanded our defensive circles. Brigadier General Eric Tremblay, spokesman for Natos International Security Assistance Force, called on the militants to lay down their arms, and said the aim of the operation was to separate the insurgents from the population. From a strategic perspective it would be better but they are under very high instructions from their senior leadership to stay and fight, and they are still under the impression that they are winning, he said. The US military sees the offensive as a potential turning point in the war in Afghanistan and a test of both the Talibans resolve and the performance of the Afghan security forces. Marjah now looks empty, most of the families have left for Lashkar Ghah or other neighbouring districts, said Kamaledine, a 50-year-old resident. Still many families are here still here. I dont have any money to take my family to somewhere safe. Haji Jamaldine, who fled with his 15-strong family to Lashkar Gah, said he had left in fear of his life. Nobody from the government has helped us yet and we are short of food and water here, he said. A member of the Red Crescent relief organisation said it had counted at least 450 families in Lashkar Gah who had arrived from Marjah, which would represent roughly 5,000 people. We are expecting more families to arrive, he said.