US President George Bush has enlisted British special forces in a final attempt to capture Osama Bin Laden before he leaves the White House. Defence and intelligence sources in Washington and London have confirmed that a renewed hunt was on for the leader of the 9/11 attacks.Delta, the US army special operations unit, and the British SBS are undertaking the main operations in Pakistan against Bin Laden.The Special Boat Service and the Special Reconnaissance Regiment have been taking part in the US-led operations to capture Bin Laden in the wild frontier region of northern Pakistan. It is for the first time that the SBS have operated across the Afghan border on a regular basis. The hunt was sanctioned by the Pakistani Government, according to a UK special forces source. It involves the use of Predator and Reaper unmanned aerial vehicles fitted with Hellfire missiles that can be used to take out specific terrorist targets. The US rarely acknowledges the use of Predator and Reaper drones, but the most recent known strike was on a suspected al-Qaeda safe house in the Pakistani province of North Waziristan earlier in June. Villagers said the house was empty. Intelligence on the whereabouts of Bin Laden is sketchy, but some analysts believe he is in the Bajaur tribal zone in northwest Pakistan. He has evaded capture for nearly seven years. A Pentagon source said US forces were rolling up Al-Qaeda's network in Pakistan in the hope of pushing Bin Laden towards the Afghan border, where the US military and bombers with guided missiles were lying in wait, according to Calcutta News .