The Federal Trade Commission on Friday ordered a divestiture in a $1.2 billion deal in the petroleum industry that was completed last year. The order forces Teppco Partners LP to sell a natural gas storage facility along with ancillary assets by the end of this year.

According to FTC officials, the 2005 merger between Enterprise Product Partners and Teppco put the natural gas liquid storage assets of both businesses under the ownership of Dan L. Duncan. That consolidation would result in higher prices and could affect service by reducing the number of commercial salt dome natural gas storage facilities in Mont Belvieu, Texas, to two from four.