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Labour MPs remain split over whether to back a further referendum on Brexit.
The party lost ground in the European elections, and some figures have called for a public vote to win back support, especially from Remainers.
Shadow home secretary Diane Abbott said another vote would be “the democratic thing to do” to move Brexit forward.
But Labour MPs representing Leave areas have warned against it, with Lisa Nandy saying it could be “the final breach of trust” with those voters.
The party agreed a policy at its last conference that if Parliament voted down the government’s withdrawal deal with the EU – which it has effectively done three times – or talks ended in no-deal, there should be