Social activist Anna Hazare and his team have decided to go on indefinite fast again at Jantar Mantar here from Wednesday to press for an effective anti-corruption Lokpal Bill. Mr. Hazare, who earlier decided not to go on fast due to medical reasons, on Tuesday gave an ultimatum to the government to meet their immediate demand of setting up an independent special investigation team (pending passage of the Lokpal Bill in Parliament) in four days or he would join the hunger strike to “fight till the finish.”