Mr Jack, who this year will celebrate 21 years in Parliament, said a desire not to "out-stay his welcome" had prompted what had been a very difficult decision.

But he added it would be business as usual until the day he actually gives up his seat.

The shock news was announced by Mr Jack at the annual general meeting of the Fylde Conservative Association at St Margaret's Church, St Annes, last night.

Steward

Today he told The Gazette: "By the next General Election, I will have served for 22 or 23 years, which is a long stint. For the time you are in office, you are a guest and you hold your seat as the steward.

"I believe in the view that guests shouldn't out-stay their welcome and I think the time should come now where I should give up this seat and someone else should come along and take over the mantle from me.

"There are other things I would like to be able to do and I think you need some good years to enjoy the rest of your life, in terms of what you want to do. And I want time to spend time with my wife Alison. People forget that Parliamentary wives are deprived of their husbands for long periods of time.

"It has been a very difficult decision to have to make. I have loved every minute of doing the job and my commitment to the job will be undiminished until the next election."

Mr Jack said he had made his announcement now in order to give the local party plenty of time to select a new candidate.

He said: "I have to give them adequate time to find someone else but I don't think there will be any difficulty in finding a quality list of candidates. Fylde is a fantastic place to represent in Parliament and a great place to live.

"It will be very difficult when the time comes to say goodbye, but for the time being, it's carry on as usual."

Mr Jack said he had no firm plans at the moment for his future after he steps down, but added he may pursue other business interests.

During his time in office he has held four ministerial roles in Social Security, the Home Office, the Treasury, and Fisheries.

Fylde is one of the safest Tory seats in the country and has been represented by Conservatives for more than 60 years. Mr Jack's predecessor Sir Edward Gardner, held the seat for 17 years, and before him, Col Claude Granville Lancaster held it for 25 years.