Methods and apparatus are provided for a network to control a power of transmissions from a User Equipment (UE) on a first Cell Group (CG) or on a second CG depending on a communication delay between the two CGs. Methods and apparatus are also provided for a UE configured with a first CG and a second CG in Carrier Aggregation (CA) operation to determine whether or not to transmit a channel conveying control information when the UE needs to reduce a respective nominal transmission power. Methods and apparatus are additionally provided for a network to transmit and for a UE to receive a Transmission Power Control (TPC) command for transmission on a cell of a first CG or on a cell of a second CG.