A fuel pump assembly for pressurizing fuel such as dimethyl ether (DME). The fuel pump assembly includes a plunger assembly and a pump block defining a pumping chamber and a plunger assembly cavity in communication with the pumping chamber. The plunger assembly is movable at least partially in the plunger assembly cavity towards and from the pumping chamber. The fuel pump assembly includes a metering valve and a suction channel located between the metering valve and the pumping chamber in an intended direction of flow of the fuel, wherein the fuel pump assembly comprises a leakage return conduit, with a first leakage return conduit opening in fluid communication with said plunger assembly cavity, adapted to return fuel that has leaked from the pumping chamber. The leakage return conduit includes a second leakage return conduit opening located in the suction channel.