New Delhi, Aug. 1 -- LONDON - A drilling campaign that started when Harold Wilson was prime minister is ending. BP announced Thursday it is putting its entire UK North Sea portfolio up for sale after six decades of continuous production, a move that puts roughly 1,100 jobs at risk and marks the oil major's most significant European retreat since it first tapped the basin in the 1960s.

the Clair and Glen Lyon fields west of Shetland, the Andrew platform, and the ETAP processing hub in the Central North Sea. Together they represent assets BP has operated through every oil price cycle since the 1973 OPEC embargo, the shale revolution, and now the current Iran-driven energy shock that has pushed Brent crude above $100 a barrel for much of th...