Expected Tory gains if changes go ahead

The Boundary Commission proposals, aimed at ensuring seats have broadly similar numbers of voters, will see England gain 10 additional seats overall, but the bulk of those will be in the South.

While experts believe the plans will result in gains for the Conservatives, the upheaval could cause problems for some senior Cabinet ministers.

Defence Secretary Ben Wallace’s Wyre and Preston North seat would be carved up, and Education Secretary Gavin Williamson could face major changes to his South Staffordshire constituency.

Labour leader Sir Keir Starmer will see his parliamentary boundaries substantially redrawn, while the seats of Prime Minister Boris Johnson and Chancellor Rishi Sunak will remain largely unchanged under the proposed new electoral map of England.

Separate reviews will propose the constituencies in Wales, which is due to lose eight seats, and Scotland, which will be down two.

Of the 533 existing English constituencies, fewer than 10% will remain unchanged under the proposals.

The Boundary Commission is not due to make its final recommendations to Parliament until July 2023 and its proposals are the subject of an eight-week consultation.

Tory peer and elections expert Lord Hayward told the PA news agency: "My thought is that the Tories' net gain will be five to 10 seats. There's much more change than I expected, and I think most people would say that.

"Obviously you've got to do a fair amount of change because what you're working on is electorates that are over 20 years old now."