Jeremy Corbyn will face his first electoral test next month as a by-election looms in the Labour-held constituency of Oldham West Royton.
The Observer newspaper reports that the opposition party will move the writ in the House of Commons for 3 December, formally triggering the one-off poll.
The seat has been made vacant after the death of longstanding MP Michael Meacher, a socialist who served as a junior minister in the last Labour government.
He had represented the seat since 1970 until his death last month aged 75 years old.
Oldham West and Royston is a nominally safe seat for Labour at general elections, with the party taking 54.8 per cent of the vote at May’s general election.
The nearest challenger was Ukip with 20.6 per cent of the vote.
The eurosceptics are expected to do well in the December poll, after they came within 2 per cent of taking the neighbouring Heywood and Middleton seat from Labour at a 2014 by-election.
Notable runners and riders to be Labour’s candidate in the by-election include Jim McMahon, the leader of Oldham Council, and Kate Godfrey, previously a Labour candidate in another seat.
Mr McMahon, who is seen as a moderate within the Labour party, is being reported in the local press as the favourite.
The date of the by-election is Labour’s choice because by convention the party who previously held the seat is allowed to move the writ in the House of Commons scheduling the poll.
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