He succeeded Dr N.M. Perera as President of the redoubtable All Ceylon United Motor Workers' Union (ACUMWU). He also set about organising the United Corporations and Mercantile Union (UCMU) which brought together workers in government corporations, and of which he was general secretary. He went around the country from factory to factory and built up a union of several tens of thousands of members. One of his lieutenants in this task was Vasudeva Nanayakkara, who became an MP in 1970. At the 1970 General Election, the UCMU also sponsored the candidature of novice Mahinda Rajapakse, who was the Chairman of its Vidyodaya University branch and who was later to become Prime Minister and then President of Sri Lanka.