ST. PAUL (AP) - Four Republican senators have asked Minnesota's highest court to prevent the judicial branch from authorizing state spending in a government shutdown.

The petition filed Monday says court-ordered funding for critical services would violate the constitutional separation of powers and infringe on the Legislature's power to appropriate money.

It says Democratic Gov. Mark Dayton is trying to soften the blow of a government closure by continuing services such as prison guards and the State Patrol.

Minnesota is headed for a shutdown starting July 1 unless Dayton and the Republican-controlled Legislature pass a new state budget.

They are at a political impasse.

The petition from Sens. Warren Limmer and colleagues also argues that the courts have no authority to order stalled budget talks into mediation, as Dayton has proposed.

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