Jeremy Corbyn, Owen Smith, and George Osborne are among the high-profile MPs whose parliamentary constituencies will disappear under a proposed shake-up of UK parliamentary seats.
Fifty out of 650 House of Commons seats are being abolished in the boundary review, which is aimed at cutting costs and making sure constituency sizes are more equal.
The new electoral map – published by the Boundary Commission on Tuesday – will be in place for the 2020 general election but it could be tweaked following a consultation.
Labour has dismissed the move as “gerrymandering” because the party is expected to lose up to 30 of the 50 seats being axed. There are also fears on the Labour benches that leader Jeremy Corbyn will use the boundary changes to deselect MPs who disagree with him.
Some Conservatives have also expressed dismay over the shake-up, warning that getting rid of 50 MPs is wrong when the number of government ministers stays the same and the House of Lords continues to grow.
The number of MPs will be cut from 533 to 501 in England, 59 to 53 in Scotland, 40 to 29 in Wales, and 18 to 17 in Northern Ireland. It means many MPs who want to stay on at the next election face a battle with their neighbours for newly created seats.
Corbyn's Islington North constituency, which he has represented since 1983, is disappearing as part of changes in north London. The neighbouring seats of his shadow cabinet allies Diane Abbott and Emily Thornberry will also be redrawn, with half of Abbott's seat becoming a new constituency called Hackney Central.
But sources close to Corbyn said he was relaxed about the changes, given that most of the new Finsbury Park and Stoke Newington seat will effectively be his old seat of Islington North.
Meanwhile Corbyn's Labour leadership rival Owen Smith is set to lose his Pontypridd seat, which is being merged with veteran Ann Clwyd's Cynon Valley constituency. Former chancellor Osborne will also see his Tatton Park seat axed as it is merged with neighbouring areas.
Other well-known MPs facing the abolition of their seats include Labour moderates Alison McGovern (Wirral South), Chuka Umunna (Streatham), and Tristram Hunt (Stoke on Trent Central). It means they could face a tough selection battle against Corbyn loyalists backed by pressure group Momentum.
The Boundary Commission released proposals for England and Wales on Tuesday, following Northern Ireland last week. Plans for Scotland will be published next month.
Under the plans, every constituency will need to have between 71,031 and 78,507 voters – excluding the Isle of Wight, Orkney & Shetland, and Na h-Eileanan an Iar (Western Isles). At the moment, seats range in size from around 21,000 to 110,000 voters.
Experts say the shake-up favours the Conservatives because the number of voters in inner-city northern seats, which tend to favour Labour, has fallen over time – while the number in suburban southern seats, which tend to be Conservative, has risen.
It means that these smaller Labour seats are more likely to be amalgamated, leaving many MPs without a constituency.
The proposed boundary changes are based on the number of people on the electoral register in December 2015. Critics warn that this excludes up to 2 million who signed up to vote in the EU referendum.
Former prime minister David Cameron tried to change the boundaries in 2013 – in a bid to “cut the cost of politics” – but was forced to drop the plans by his Liberal Democrat coalition partners.
Conservative party chair Patrick McLoughlin said: "Boundaries should be drawn up in an impartial and independent way, so I welcome the Boundary Commission’s proposals to implement parliament’s instruction to ensure equally sized constituencies. Without these reforms, MPs could end up representing constituencies based on data that is over 20 years old."
But Jon Ashworth, Labour’s shadow minister without portfolio, said: "The current proposals to redraw constituency boundaries are unfair, undemocratic, and unacceptable. They are based on an out-of-date version of the electoral register with nearly 2 million voters missing.
"Constitutional changes should be done fairly and consensually, to ensure that everyone is given a voice. There is nothing fair about redrawing boundaries with millions left out, and reducing the number of elected MPs while the unelected House of Lords continues to grow.
"These changes are not about fairness to voters, they are about what is best for the Tory party and they must not go ahead. The commission must rethink and ensure that no elector loses out."
Emily Ashton is a senior political correspondent for BuzzFeed News and is based in London.
Contact Emily Ashton at firstname.lastname@example.org.
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