North East Herts MP Sir Oliver Heald, who has served in the House of Commons for 32 years, has announced that he will not be standing as a candidate at the next general election.
Sir Oliver has written to the chairman of North East Herts Conservative Association, Lynda Needham, and notified the Prime Minister to explain his decision.
The MP, 69, explained that at his stage of life he wishes to spend more time with his grandchildren and to be able to help his family.
He has also made clear that he will continue to campaign for the Conservatives and is a loyal supporter of the Prime Minister.
Sir Oliver said: "It has been a great privilege to serve the people of this wonderful constituency since 1992 and to have won the confidence of the majority of electors in eight general elections.
"I shall continue to work hard for the people of North East Hertfordshire until the election and I shall continue to support the Conservative cause and the Prime Minister.
"I look back with pride on the many individuals I have been able to help over the years with a multitude of different personal problems.
"I have supported the construction of three major bypass projects, campaigned successfully for rail station improvements and secured funding for better school buildings. I was also pleased to press for investment at Lister Hospital, together with the Stevenage MP.
"Our local environment is very precious and I have been at the forefront of the campaign for improving the health of our chalk streams.
"In Parliament, two constituency cases have led directly to two Private Member's Bills - one to protect service animals (Finn's Law) and the other last week, to improve conditions for parents whose children are in hospital for long periods."
Sir Oliver highlighted how, as Pensions Minister under John Major, he was able to bring in new laws to protect pensions schemes from the "actions of predatory employers" and, as Solicitor General in David Cameron's government, he started the modernisation and digitisation of the courts. "I also took cases with unduly lenient sentences to court successfully," Sir Oliver said.
He continued: "As a Justice Minister during Theresa May's time, I introduced new ways of helping vulnerable witnesses to give their evidence.
"It has been a long and full career, but my main focus has always been on serving my constituents in North East Hertfordshire.
"I have been supported magnificently throughout the years by a small team of dedicated staff and, of course, by the Conservative councillors and party members, to whom I am deeply grateful."
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