The boss of the UK’s largest trade union has accused the Labour leadership of “trading” seats intended for female candidates in order to allow “favourite sons” to take up the safest Labour seats set to be vacated at the next election.

In an extraordinary broadside at senior party figures, Unison general secretary Dave Prentis urged Jeremy Corbyn to intervene, alleging that the party was covertly using all-women shortlists (AWS) as “bargaining chips” and was stitching up selections in favour of chosen men.

Prentis’s letter, which was leaked to the Guardian, said that the tactics risked the party’s advances in electing more female MPs and using all-women shortlists in any seats where a female MP had stood down.

“In recent weeks, however, I am aware of discussions and ‘negotiations’ around the existing seats that seek to overturn that practice, flipping AWS seats and trading them around for what appears to be favourite sons taking up the safest seats,” Prentis wrote. “This I find deeply concerning and wish to flag up the inherent risks and dangers of meddling with a process that has served us reasonably well to date.”

Prentis did not name the favoured male candidates he alleged were seeking safe seats. However, he said he believed the party risked alienating female candidates because of the alleged politicking around parliamentary selections, including “strong, talented women” in his own union.

“What we are witnessing at the moment is the current all-women shortlists being used as bargaining chips primarily for the convenience of men to take or monopolise promised seats,” he wrote.

“After all our work over the decades we cannot return to the bad old days of backroom stitch-ups and women being pushed further away.”

Prentis said Corbyn had given “personal support over the years” to all-women shortlists and urged him to “intervene and voice your opposition to any changes being made that threaten or seek to diminish the existing AWS arrangement”.

Unison employees who have become MPs include high-profile figures like the shadow education secretary, Angela Rayner, and Eleanor Smith, a former nurse who became the West Midlands’ first African-Caribbean MP after winning the seat once held by Enoch Powell.

Labour has recently ramped up selections for seats that are being vacated by sitting MPs at the next election, as well as those where MPs have defected to other parties.

Last week, Labour members selected Momentum-backed Navendu Mishra, a member of the governing national executive committee, to fight the next election in Stockport, the seat currently held by Ann Coffey who left Labour to join Change UK. Mick Whitley, who was backed by Unite and Unison, won the selection to fight Frank Field’s seat in Birkenhead after the veteran MP left the party.

A party spokesperson said: “Labour has more women MPs than all other political parties combined and we are committed to improving diverse representation at all levels of the party. In the next general election, women candidates will be standing in more than two thirds of our key target seats.”



A party source said that 72 female candidates had been selected out of the 102 target early selection seats for the next election.