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PNV and EA, the later of which had split from the former in 1986, reached an electoral coalition agreement on 13 March 1999, in order to counter the electoral ascendance of both the People's Party of the Basque Country and Euskal Herritarrok. The alliance was disbanded after EA's leadership voted on 31 August 2006 not to preserve the coalition ahead of the 2007 local elections.