The United Democratic Front (UDF) is the Indian National Congress-led alliance of centre to centre-right political parties in the Indian state of Kerala. It is one of the two major political alliances in Kerala, the other being Communist Party of India (Marxist)-led Left Democratic Front, each of which has been in power alternately since 1980 E. K. Nayanar ministry. Most of the United Democratic Front constituents are members of the Indian National Congress-led United Progressive Alliance at pan-India level. United Democratic Front was created by the Indian National Congress (then known as Congress-Indira) party leader K. Karunakaran in 1979, as a successor to the existing Congress-led alliance. The alliance first came to power in 1981 (K. Karunakaran ministry) and has won elections to the state legislature of Kerala in the years 1982 (Karunakaran ministry), 1991 (Karunakaran and A. K. Antony ministries), 2001 (Antony and Oommen Chandy ministries), and 2011 (Oomen Chandy ministry). The alliance currently acts as the opposition in the state legislature of Kerala (after the 2021 legislative assembly election). United Democratic Front leaders V. D. Satheesan and K. Sudhakaran currently serves as the Leader of the Opposition and Kerala Pradesh Congress Committee President respectively. The alliance currently consists of Indian National Congress, Indian Union Muslim League, Kerala Congress (Joseph), Kerala Congress (Jacob), Revolutionary Socialist Party and a variety of other smaller parties. The alliance follows big tent policy and includes a variety political parties.