The present invention relates to a crosslinkable polymer composition comprising (A) a high density ethylene homo- or copolymer having a density, determined according to ISO 1183, of at least 930 kg/m3, and (B) a copolymer of ethylene with a silane groups-containing comonomer having a content of silane groups- containing comonomer of not more than 4.0 wt%, wherein the polymer composition passes the tracking resistance test, determined according to IEC60587 (2007), method 2A at 4.5kV for 1h and 4.75 kV for 1h on compression molded plaques prepared according to ISO 11357. The present invention further relates to a track resistant wire or cable, preferably a power cable or an optical cable comprising at least one layer of the above polymer composition or to the use of the polymer composition in a wire or cable for increasing track resistance, and/or for increasing fire retardancy along the length of the wire or cable. The present invention further relates to a method for manufacturing the above polymer composition, comprising a step of compounding or dry blending the high density ethylene homo- or copolymer (A) and the copolymer of ethylene with a silane groups-containing comonomer (B).