In 1983, Dalton gave notice to Personnel Department that he intended to stand as Conservative candidate for the Richmond, North Yorkshire constituency in the 1983 general election.

However, he withdrew his candidacy for the seat before the story broke of his sister-in-law Sara Keays' affair with Trade and Industry Secretary Cecil Parkinson, and was posted as Head of Chancery to Muscat, Oman, in 1983.

He was appointed Head of Personnel in the Foreign and Commonwealth Office (FCO) in 1998, and was sent as Britain's Ambassador to Libya in 1999, when diplomatic relations were resumed after a 17-year break.

[5] Following his retirement from the FCO in 2006, Sir Richard Dalton became an associate fellow on the Middle East and North African programme at the international affairs organisation, Chatham House[6] where he heads the Libya Working Group, set up in February 2011.

Among them is the possibility that a successful appeal by Megrahi would plunge Britain, the United States and Libya once again into the fraught environment of an international investigation to find new Lockerbie suspects", Sir Richard said.