Didn’t Thatcher sell off the North Sea oil fields?
The history of government involvement in North Sea Oil & Gas is complicated but essentially the Labour government set up the state-owned British National Oil Corporation (BNOC) in the mid-70s which was then part-privatised by the Conservatives in the early-80s, becoming Britoil, with the government initially retaining a hefty share. The mid-80s collapse in oil prices led to disposal of their share and Britoil was eventually acquired by BP.