South Staffordshire Tory MP Sir Patrick Cormack, one of the longest-serving and most respected Members in the Commons, has announced he will not be fighting the next general election.
Sir Patrick, 70, said in a statement that the “unhappy events” of recent months had made working hours at Westminster much more of a burden than before.
He said: “It is also becoming increasingly clear that the new House of Commons will be very different from the old.
“Sadly, I have come to the conclusion that it is right that I should hand the torch to a younger man or woman.”
He said this was “the most difficult decision” of his life, but insisted “I am not retiring - I am merely changing direction”.
The news will come as a blow to Tory leader David Cameron, as Sir Patrick - the second longest-serving Tory MP after Sir Peter Tapsell - has a wealth of Parliamentary experience behind him and probably knows more about the House of Commons, its ways and its history, than any other Member.
Sir Patrick, who has been described as a politician, historian, journalist and author, entered Parliament as MP for Cannock in 1970, ousting Jennie Lee, widow of Aneurin Bevan, founder of the National Health Service.
He transferred to South West Staffs (now known as South Staffs) in February 1974, a seat he has represented ever since.
Sir Patrick was knighted in 1995 for services to Parliament, and in 1997, after 27 years as a backbencher, he was promoted to shadow deputy leader of the Commons. He resigned in 2000 to run for the Speakership but was unsuccessful, as he was again in a second bid for the Speakership earlier this year.
He said: “I have been immensely proud to have been a Staffordshire Member in the world’s greatest Parliament for close on 40 years, much more than half my life.”