Wiesbaden, Germany - Plans for a provincial alliance between Germany's co-ruling Social Democrats (SPD) and the small opposition Left party foundered Monday, with dissenting legislators in the state of Hesse saying they would not vote for it.

The fragile link-up, drafted by the state SPD leader Andrea Ypsilanti, had been described by opponents as possibly a model for a federal government after a general election in September next year.

The SPD is reluctant to continue its coalition with Christian Democratic Chancellor Angela Merkel past that date. The Left is anathema to many western voters because of its roots in the old East German communist party.

Dagmar Metzger, a state SPD legislator who has already said she would not not back Ypsilanti on grounds of conscience, announced Monday that she and three others would leave the SPD group in the state parliament.

That would deprive Ypsilanti's planned government of a majority.

She named the other dissenters as Juergen Walter, Silke Tesch and Carmen Everts and said they would make a joint statement at a later news conference.

Ypsilanti and the state's Greens party had gradually agreed over the past few weeks to form a minority government to be "tolerated" by the Left, meaning Left legislators would back the state government in key votes.

The new coalition had been set to oust the incumbent state premier, Roland Koch, a Christian Democrat, on Tuesday and vote Ypsilanti to take his place in the state capital, Wiesbaden.

"There won't be any vote tomorrow," Metzger told Deutsche Presse-Agentur dpa in Wiesbaden.

Koch has hung on in power since a tied election January. Merkel was eager to keep him in place after another ally, the Christian Social Union in Bavaria, lost its absolute majority in state elections on September 28.

To date, the Social Democrats have only formed coalitions with the Left in eastern Germany, where the Left is strongest. (dpa)