Energy production and logistics company Phillips 66 is to sell its interests in two natural gas pipeline systems and a refined products system to its affiliate Phillips 66 Partners for a total of $1.01 billion.

The partnership was formed by Phillips 66 in 2013 to acquire, own and operate crude oil, refined petroleum product and natural gas liquids pipelines and terminals and other transportation and midstream assets.

Phillips 66 Partners said on Monday that it has agreed to purchase Phillips 66's one-third equity interests in the limited liability companies that own the Sand Hills and Southern Hills natural gas liquids (NGL) pipeline systems, and a 19.46 percent equity interest in Explorer Pipeline Company, which owns the Explorer refined products pipeline system.

Sand Hills is a 720-mile NGL pipeline system that runs from Texas' Permian Basin and Eagle Ford Shale to the Gulf Coast. It has a capacity of 200,000 barrels per day and can be expanded up to 350,000 barrels per day with additional pumping stations.

Southern Hills is an 800-mile NGL pipeline system running from the Midcontinent area to the Gulf Coast, with a capacity of 175,000 barrels per day.

The 1,830-mile Explorer refined products pipeline system has a capacity of 660,000 barrels per day, providing connectivity to refineries and market centers from the Gulf Coast to the Midwest.

"This acquisition will expand our fee-based portfolio into NGL transportation and provide us with an interest in one of the largest refined products pipeline systems in the U.S.," commented Greg Garland, chairman and CEO of Phillips 66 Partners.

The deal, which is set to close early next month, is expected to be immediately accretive.