Jeremy Corbyn, George Osborne and Boris Johnson are among high-profile politicians who will see their seats redrawn in a dramatic shakeup of the country’s electoral map that will alter the constituencies of more than 500 MPs.
Overall, Labour is worst hit by the shifting boundaries, which are part of an effort to cut the number of politicians in parliament from 650 to 600, with significant changes for MPs including Yvette Cooper, Tristram Hunt and Owen Smith. Many opposition politicians will fear that local members will take the opportunity of a shakeup to try to deselect them if Corbyn retains the leadership later this month.
The angry responses came after the proposals from the Boundary commissions for England and Wales were handed out on Monday.
The results, which aim to equalise the number of voters in each constituency, will pit MPs against each other in a battle for survival – and not only those in the Labour party.
Despite giving the Tories an electoral boost overall, the plans could create a headache for Theresa May as up to 17 of her MPs lose their current constituencies – the same number as the party’s working majority.
Among the worst hit are the previous chancellor, George Osborne, whose Tatton constituency is broken apart. Priti Patel, Justine Greening and David Davis are three other Conservative cabinet ministers who are also likely to be affected. Patel will need to be parachuted into another Essex seat, vacated by a retiring colleague.
Johnson, the foreign secretary, will have to contest a newly created constituency in west London with more wards that have voted Labour, although his popularity is likely to mean he wins again.
Jon Ashworth, who is a key shadow cabinet minister leading on the policy, called the proposals “unfair, undemocratic and unacceptable”.
He said it was wrong for the calculations to be based on the electoral register at the end of 2015, meaning that 2 million voters who signed up in the run-up to the EU referendum result are not included.
“Constitutional changes should be done fairly and consensually, to ensure that everyone 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,” he said, calling for the policy to be blocked.
The proposals were also condemned for threatening to “skew our democracy” by the Electoral Reform Society. Katie Ghose, chief executive of the group, said it meant areas with the lowest levels of registration were getting a bad deal.
“Young people, some ethnic minority groups and those in the private rented sector are all less likely to register to vote than others. That makes many of them effectively cut out of the new political map,” she said.
Some urban MPs argue that their seats may have fewer people on the electoral register but many more not signed up.
Labour is also worried about Wales where every seat has been changed, and the party could lose a number of sitting MPs. Stephen Kinnock, who represents Aberavon, said the Welsh commission had divided his high street from the main shopping centre, and the Port Talbot steelworks from where its workers lived in an “absurd” decision. “It is a brutal mathematical strategy and a barefaced gerrymander,” he said.
For the Conservatives, May’s seat is unchanged, with her chancellor, Philip Hammond, facing minimal disruption. However, his predecessor Osborne will be forced to look for a new seat to stand in the 2020 general election.
“It’s very important that the boundaries of constituencies are changed periodically to reflect changes in the population – and it’s very unfair at present that not all constituencies are of equal size. So I fully support the Boundary Review as a part of our democracy,” said Osborne.
“We’ve now seen the first draft of the proposals. It involves big changes for my constituency. I’m going to consider carefully whether they can be improved upon and whether to make representations. Whatever the final boundaries, I look forward to putting myself forward to voters for re-election for Cheshire in 2020.”
Patrick McLoughlin MP, Tory chair, said his party would follow a “no colleague left behind” policy under which MPs would be given the opportunity to stand in new seats.
“This constructive approach is in strong contrast to the Labour party, which is riddled with infighting and threats of deselection. Momentum’s aim to use this process to boot out moderate Labour MPs is not an argument against these vital reforms, which will ensure fairness across the United Kingdom.”
The Boundary Commission for England was keen to stress that the new maps were just proposals.
Sam Hartley, secretary to the commission, said: “They are just the commission’s initial thoughts during the next 12 weeks. We want people to take a look and tell us what they like and don’t like about our proposals.” In a previous attempt to redraw boundaries under Cameron major changes were made to the initial plans.
These proposals hit London most sharply, with only four out of 73 seats untouched, but other areas are also heavily affected with just six seats left unchanged in the eastern region, three in the north-east and seven in the West Midlands.
At a packed, if brief, parliamentary Labour party meeting on Monday evening, the MPs listened largely in silence to a discussion of the boundary changes, which dominated proceedings.
A Labour source said the meeting had been largely sober and thoughtful, not least as MPs had only recently seen the proposed changes for their seat, and had yet to properly absorb the full picture.
There was one moment of lightness when an MP, leaving the meeting, told reporters as he left: “All women shortlist in Islington, that’s what we want,” a reference to Corbyn’s seeming battle to keep a seat.
Under Labour rules for deciding who represents rejigged constituencies, MPs need more than 40% of the seat to contain their existing constituents to have a chance to compete for it.
The Labour source said it was not yet known how many potential such two-way battles for new seats could emerge: “It’s far too early to say. We need to have a closer look at everything.”
The Conservatives claim the changes will address a historic imbalance that favoured Labour unfairly.
Chris Skidmore, minister for the constitution, said: Equalising the size of constituencies in the Boundary Review will mean everyone’s vote will carry equal weight. Without such boundary reforms, MPs could end up representing constituencies based on data that is over 20 years old, disregarding significant changes in demographics, house building and migration.
As it stands, some constituencies have twice as many electors than other constituencies and this cannot be right.