The measurement of the poloidal velocity of rotation (Vpol) in tokamaks is of interest for several reasons: the most important being that Vpol enters the formula for the radial electric field Er multiplied by the large toroidal magnetic field, which makes possible a non-negligible contribution to Er as soon as Vpol increases above a relatively small value. On its side, through sheared E¥B flow, Er is thought to be fundamental for determining confinement. In this work we present the spectroscopic diagnostic system that has recently been set up to measure core Vpol for intrinsic (carbon) or extrinsic (helium) impurities at JET. We will show the first results obtained when measuring Vpol in discharges where ITBs, ICRH or both are present, compare our results with neoclassical calculations performed for the same conditions, and find that the two results are, within the experimental errors, in reasonable agreement.