Embodiments of the present disclosure provide a method in a base station for coordinating resources in a wireless communications system with carrier aggregation in which a first group of terminal devices is served by a primary cell and one or more secondary cells under control of the base station. The method comprises obtaining information indicating arrival of a second group of terminal devices at coverage of the base station. A speed of any terminal device of the second group is higher than a speed of any terminal device of the first group. The method also comprises releasing resources on at least one secondary cell of the one or more secondary cells and allocating the released resources to the second group of terminal devices.