In August 1941, the 1st Cavalry Division was reorganised as the 10th Armoured Division. Clark remained in command until April 1942 so missing the division's active service at Alam Halfa and Second Battle of El Alamein. He became GOC Lines of Communication in Tunisia and thereafter Deputy Governor of Sicily after its capture in 1943. At the end of 1943 he briefly became Major-General Administration at GHQ Middle East in Cairo before becoming Chief Administrative Officer at Allied Forces Headquarters (AFHQ) for which he held the acting rank of lieutenant-general.