LABOUR leader Jeremy Corbyn's Islington North constituency is one of 50 to be abolished at the next general election, under proposals published by the Boundary Commission for England.

A shake-up of seats in north London sees the constituency which Mr Corbyn has represented since 1983 divided in two, potentially pitting him against two of his closest lieutenants - shadow health secretary Diane Abbott and shadow foreign secretary Emily Thornberry - in the race for selection as candidates for the new seats of Islington and Finsbury Park & Stoke Newington.

Mr Corbyn said he was "very unhappy" about boundary changes which could affect his constituency in North London.

Speaking as he arrived for a private dinner with the TUC general council in Brighton, he said he was "very confident" about the future, adding there was a long way to go before any suggested changes came into effect.

"I look forward to representing some parts of Islington, " he said, adding he was very unhappy about the suggested size of a new constituency.

Meanwhile, Mr Corbyn's leadership rival Owen Smith sees his Pontypridd seat merged with the neighbouring Cynon Valley constituency of veteran backbencher Ann Clwyd.

Mr Smith is one of a number of prominent critics of the current leadership who could face a fight to ensure selection for the 2020 election by constituency associations swollen by the ranks of Corbyn supporters over the past year. Even if Ms Clwyd, 79, decides to step down, Mr Smith is far from certain of inheriting the new constituency in south Wales.

Chuka Umunna (Streatham), Yvette Cooper (Normanton, Pontefract and Castleford) and Tristram Hunt (Stoke-on-Trent Central) are among leading moderates facing significant changes which could leave them vulnerable to de-selection attempts by hardline Corbyn supporters.

The planned reduction of the size of the House of Commons from 650 to 600 MPs is expected to hit Labour hardest, with more constituencies abolished or merged in strongholds such as London, Wales, the North-East and North-West than the Tory-dominated shires.

The party has signalled it will fight the "unfair, undemocratic and unacceptable" changes, stressing they are based on an "out of date" version of the electoral register based on populations recorded in the electoral roll for 2015 and missing two million voters who signed up to vote in the EU referendum.

Labour shadow minister Jon Ashworth 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 two million voters missing.

"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.

"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."

The Maidenhead seat of Prime Minister Theresa May remains as it is, while Chancellor Philip Hammond's Runnymede and Weybridge is largely unchanged.

Foreign Secretary Boris Johnson (Uxbridge and South Ruislip) faces a substantial redrawing of the electoral map, but would appear well-placed to secure the Conservative nomination for the new seat of Hillingdon and Uxbridge. The seats of Cabinet colleagues such as Liam Fox, Jeremy Hunt and Amber Rudd escape unscathed, but Brexit Secretary David Davis sees his Haltemprice & Howden constituency in East Yorkshire cut in two.

Sources close to Mr Corbyn dismissed suggestions that he would lose his home base under the changes, saying there was "every reason to believe Jeremy will still have a seat to contest" as 60% of the new Finsbury Park & Stoke Newington constituency is made up of areas currently in Islington North.

However, if confirmed, the changes look likely to cause headaches for senior Labour figures in north London, with the creation of a new Hackney Central seat made up of five wards each from the current constituencies of Ms Abbott and Commons Public Accounts Committee chair Meg Hillier.

Conservative chairman Sir Patrick McLoughlin said the party would follow a policy of "no colleague left behind" to minimise the disruption to sitting MPs.

"This constructive approach is in strong contrast to the Labour Party which is riddled with infighting and threats of deselection," said Sir Patrick. "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."

Liberal Democrats said they were "confident" of holding all of their eight seats under the proposals and gaining at least one in Cambridge. But a spokesman said the party had "serious concern" about using the "out of date" electoral roll.

"Tory claims that this process will lead to 'equal votes of equal value' are plain wrong," said a Lib Dem spokesman. "This process will still leave a plethora of safe seats across the country, and millions of votes which don't count."

Greens, who see significant changes to their only seat - co-leader Caroline Lucas's Brighton Pavilion - said that only a Government with a "profoundly skewed" set of priorities would push ahead with the changes while ignoring the "deep-rooted sickness" of an unelected second chamber and non-proportional voting for Westminster elections.

The initial proposals for England and Wales, announced on Tuesday, follow those for Northern Ireland which were disclosed last week. Plans for Scotland are due to be published on October 20. Final proposals are due in October 2018 for use in the general election scheduled for May 2020.

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 each constituency - with a couple of exceptions in the Isle of Wight, the Western Isles and Orkney and Shetland - have broadly similar populations.

Constitution minister Chris Skidmore said the Government was "committed to ensuring fair and equal representation for the voting public across the UK is in place by the next general election". The process would save taxpayers £66 million over five years by cutting the number of MPs.

"Our democracy and our parliamentary system need to represent everyone equally," said Mr Skidmore. "That's why the independent Boundary Commissions are proposing measures to achieve equal-sized constituencies that will ensure an equal say for each voter. As it stands, some constituencies have twice as many electors as other constituencies and that cannot be right."

Some other points that have emerged so far from the England Boundary Commission's initial proposals:

:: Ukip's sole MP Douglas Carswell sees half his Clacton constituency taken away in a shake-up with the establishment of a new Harwich & Clacton seat.

:: Tory former chancellor George Osborne's Tatton constituency is axed, with a small remnant going into a new Altrincham & Tatton Park seat.

:: Among historic seats to go, the Rushcliffe constituency represented by Tory former cabinet minister Ken Clarke since 1970 is set for abolition.

:: Commons Speaker John Bercow sees minor changes to his Buckingham constituency in which he originally was elected as a Conservative.

:: There is no change to Tory former prime minister David Cameron's seat of Witney, where a by-election is now due to take place after his decision to step down as an MP.

:: The Batley & Spen constituency of Labour's Jo Cox, who died in June after being shot and stabbed, will disappear, to be replaced by two new seats: Batley & Morley, and Spen. A by-election is also pending here.