The decision sets a precedent and could add as many as 126,592 members to the list of eligible voters in the leadership race.
Criticism of the embattled Labour leader has been mounting in the wake of the June 23 vote for the United Kingdom to leave the European Union, which dealt a blow to its economy. Days later, Corbyn lost a no-confidence vote by a wide margin but refused to resign and said he would take part in the party leadership election.
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