Change of the toroidal plasma rotation induced by directed waves in the Ion Cyclotron Range of Frequencies (ICRF) has been identified experimentally for the first time on the JET tokamak. The momentum carried by the waves is initially absorbed by fast resonating ions, which subsequently transfer it to the bulk plasma. Thus, the results provide evidence for the influence of ICRF heated fast ions on plasma rotation. Plasma rotation can have beneficial effects on the performance of tokamak plasmas. In particular, rotation can influence the MHD stability and increase the stabilising effect of a resistive wall. Furthermore, it is believed that the shear in the toroidal velocity component associated with the radial electric field can suppress turbulence and thereby create transport barriers. It is therefore important to investigate mechanisms that can induce plasma rotation.