In August 1944 Ponnambalam formed the All Ceylon Tamil Congress (ACTC), the first political party to represent the Ceylon Tamils, from various Tamil groups. He was elected president of the party. Ponnambalam stood as the ACTC candidate for Jaffna at the 1947 parliamentary election. He won the election and entered Parliament. The ACTC swept the poll in the Tamil dominated Northern Province, winning seven of the nine seats in the province. The United National Party (UNP) became the largest party Parliament but it did not have a majority. Ponnambalam presided over a meeting at the house of Herbert Sri Nissanka (the Yamuna Conference) at which an unsuccessful attempt was made to form a government without the UNP. The UNP subsequently formed a government with the support of independent and appointed MPs.