On 24 May 2005 Lafontaine left the SPD. After two weeks of speculation it was announced on 10 June that he would run as the lead candidate for The Left party ("Die Linke"), a coalition of the Labor and Social Justice Party (WASG), which was based in western Germany, and the Left Party.PDS, which was the successor to the ruling East German Socialist Unity Party (SED). Lafontaine joined the WASG on 18 June 2005 and was selected to head their list for the 2005 Federal Election in North Rhine-Westphalia on the same day. Moreover, he also unsuccessfully contested the Saarbrücken constituency, which he had previously represented from 1990 to 2002. Nevertheless, the result of the Left party in the Saarland was by far the best in any of the federal states in the West of Germany.