Thatcher official warned of 'unscrupulous practices' after stock exchange deregulation

Margaret Thatcher's most senior official warned privately that her financial sector reforms were giving birth to a new culture of corner-cutting and "unscrupulous" practices in the City, according to newly-released UK government papers.

Robert Armstrong, the Cabinet secretary, took the unusual step of setting out his personal concerns about "the things that people think are going on in the City" in a highly prescient memorandum to No 10.