LONDON (Dow Jones)--BP PLC (BP) will shut its Unity Riser platform in the North Sea Aug. 1 for three or four days of maintenance, a spokesman said Monday. The Unity Riser platform is a key part of Forties Pipeline System, operated by BP. It connects many fields, including Britannia, Scott, Nelson, Elgin/Franklin and ETAP, to the main oil line to Scotland. Some technical problems occurred recently on the FPS. Early last week, "a valve failure" on the system prompted Nexen Inc. (NXY) to shut its Scott platform in the North Sea. -By Sherry Su, Dow Jones Newswires; +44(0)20-7842-9329; [email protected] (END) Dow Jones Newswires July 19, 2010 08:02 ET (12:02 GMT)