Emily Thornberry has outflanked Sir Keir Starmer in the race to succeed Jeremy Corbyn as the next Labour leader by showing “leadership” in championing Remain at its party conference, a shadow cabinet minister said.

The shadow foreign secretary has made a succession of prominent interventions at the party conference in Brighton as she pushed for Labour to back staying in the European Union.

Senior shadow cabinet members are carefully positioning themselves amid mounting concern that Labour will lose the general election and Mr Corbyn will be forced to stand down.

A shadow minister told The Times that colleagues have serious concerns that both the Tories and Labour will lose ground at the next election, with the Liberal Democrats picking up significant numbers of seats.

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