The invention relates to a an air supply arrangement (100) for supplying air from the atmosphere towards an internal combustion engine in a vehicle, the air supply arrangement comprising an air intake (101) for intake of air from the atmosphere, an air outlet (102) for outlet of air towards the internal combustion engine, and an air duct (103) for leading air from the air intake (101) in a downstream direction to the air outlet (102). A separator (200) is arranged in the air duct (103) so as to divide the air duct (103) into an upstream portion (104) and a downstream portion (105) for filtering of atmospheric air from debris by passage of said atmospheric air through the separator (200). The air supply arrangement (100) further comprises a compressed air delivery arrangement (300) being arranged to supply compressed air towards the separator (200) for cleaning the separator (200) from assembled debris.