Under the Project E MOU, US personnel had custody of the weapons. This meant they performed all the tasks related to their storage, maintenance and readiness. The bombs were stored in Secure Storage Areas (SSAs) on the same bases as the bombers which British staff were not permitted to enter. It was therefore impossible to store British and Americans bombs together in the same SSA. US custody also created operational problems. The procedure for handing over the bombs added an extra ten minutes to the bombers' reaction time, and the requirement that US personnel had guardianship of the weapons at all times meant that neither they nor the bombers could be relocated to dispersal airfields as the RAF desired. The operational restrictions imposed by Project E "effectively handed the US government a veto over the use of half of Britain's nuclear deterrent".