ST. PAUL (AP) - Ramsey County officials say they have a deal with the federal government to buy the 430-acre parcel in Arden Hills where the Minnesota Vikings want to build a new stadium.

County commissioners say Thursday they got a formal purchase offer for the former Army ammunition plant site. Commissioner Rafael Ortega says the county will buy the land for $28.5 million and has until August 1, 2012 to cancel the purchase without penalty if a stadium deal doesn't come together in Ramsey County.

The Vikings hope to build a $1.1 billion stadium on the land with help from a state subsidy.