A natural gas supplier is planning a $53 million, 15-mile expansion to connect the liquefied natural gas terminal under construction in Pascagoula to a main line in Mobile County in neighboring Alabama.

Preliminary expansion plans call for placing about 4.45 miles of the 26-inch pipeline in Mobile County, with the other 10.85 miles in Jackson County, Miss., said officials from Tulsa, Okla.-based The Williams Cos., which owns the Transco pipeline.

Williams and Florida Gas Transmission Co. are partnering for the expansion to connect Gulf LNG Energy’s liquefied natural gas import terminal in Pascagoula’s Bayou Casotte with the Mobile Bay Lateral portion of Transco’s pipeline.