During World War II the Comintern sent him back to Vardar Macedonia (being then part of the Kingdom of Yugoslavia under the name 'Vardarska Banovina') to serve as a Secretary of the Macedonian Regional Committee of the Yugoslav Communist Party (YCP) since 1940. After the Bulgarian takeover of Vardarska Banovina in April 1941, the Vardar Macedonian communists fell in the sphere of influence of the BCP under Sharlo's leadership.
As a result of World War II, the Comintern sent him back to Vardar Macedonia (which was then part of Yugoslavia and known as 'Vardarska Banovina') in 1940 to work as the Secretary for the Macedonian Regional Committee of the Yugoslav Communist Party. After Bulgaria took control of Vardarska Banovina in April 1941, the communist forces in the region became aligned with the BCP under Sharlo's leadership.