Proposals to merge the Essex constituencies of Witham and Maldon at the next general election could see one of two senior Tories lose their seat.

A shake-up of boundaries in Essex – the only region in the East of England facing the prospect of losing a constituency – could result in the merger of the two neighbouring seats.

The proposals, published by the Boundary Commission for England, potentially pit Witham MP Priti Patel against Maldon MP John Whittingdale in the race for selection as candidates for the new seat.

There were no significant proposals affecting Suffolk. All seven constituencies are set to remain largely unchanged.

The news comes amid a planned reduction of the size of the House of Commons from 650 to 600 MPs.

In Essex, the number would drop from 18 to 17 if the proposals are approved.

Ms Patel said: “The Boundary Commission has put forward its initial proposals on the new Parliamentary boundaries for public consultation.

“This is an independent review of the constituency boundaries and I would encourage anyone interested in the boundaries to look at the proposals and respond to the consultation.

“When boundary reviews take place people often have strong views about their communities and identities and they should have their say.

“It is important for people to know that these are only proposals and no changes will come into effect until the next General Election in 2020.

“Local residents and businesses can be assured that I will continue to represent all parts of the current Witham constituency.”

Mr Whittingdale did not comment despite requests.

The Boundary Commission for England report, entitled ‘Initial proposals for new Parliamentary constituency boundaries in the Eastern region’, stated: “We propose that the Maldon constituency transfer one ward to the constituency of Basildon and Billericay and five wards to the constituency of Rayleigh and Woodham Ferrers

“To compensate for this transfer and the fact that the electorate is currently 68,924, we propose to include in this constituency 10 wards to the north and west of Maldon.

“Much of this change to the Maldon constituency is due to the fact that we have to reduce the number of constituencies in Essex by one.

“As this constituency now includes nine wards from the former Witham constituency, we propose to call it Witham and Maldon.”

The number of MPs will be cut from 533 to 501 in England, from 59 to 53 in Scotland, from 40 to 29 in Wales, and from 18 to 17 in Northern Ireland, with the aim of ensuring that all constituencies have broadly similar populations.

The move could save taxpayers £66million over five years nationwide, constitution minister Chris Skidmore said.

The proposals also include:

-Pairing Harwich with Clacton in a new Harwich and Clacton constituency. It would fall within the district of Tendring.

- A proposed North East Essex constituency which “completely surrounds the Colchester constituency”.

It would comprise 13 wards from the Borough of Colchester and 10 wards from the district of Tendring.

Villages Point Clear, St. Osyth, Seawick and Jaywick would not be included in a constituency with Clacton.

- Moving East Donyland from Harwich and North Essex to Colchester.

- Moving Kelvedon, Feering, Silver End, Coggeshall and Black Notley into a revised Braintree constituency.

- Moving the Pinewood ward from South Suffolk to Ipswich.

- Moving Rattlesden, Onehouse and Ringshall from Bury St Edmunds to South Suffolk.