Britain's opposition Labour Party is allowing its current leader Jeremy Corbyn to be automatically included in the leadership contest.
Corbyn has been challenged for the leadership by former shadow minister Angela Eagle.
Some argued that he needed support from at least 51 Members of Parliament and Members of the European Parliament to qualify for the ballot.
Our UK Correspondent Olly Barratt says this is a pivotal moment for the opposition party.
IN: Huge news...
OUT: ...want him to go.
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Our UK Correspondent Olly Barratt says the ruling Conservative Party may take advantage....
IN: The Conservative...
OUT: ...perfect opportunity.
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