He qualified for the ballot at the last minute, nominated by 36 MPs, the majority of whom did not support him but felt that the party should be able to vote on a wider range of candidates.

[18] A leadership challenge was then much discussed in the British press in November due to a split in the parliamentary party over the prospect of Britain's participation in air strikes in Syria.

[20] The Guardian reported that "a small group of Labour MPs and advisers had been telling journalists for months to 'expect movement' against Corbyn on 24 June.

"[21] The pressure on Corbyn intensified as a result of the European Union referendum and dissatisfaction with his level of support for the losing Remain campaign.

[21] On 25 June, a 'Saving Labour' campaign website was created, to encourage members of the public to email MPs to urge them not to back Corbyn.

[25] The Scottish National Party sought to argue that they should become the official Opposition in the Commons with Labour unable to fill the role.

[28] Angela Eagle, a former member of his Shadow Cabinet who resigned after Benn's sacking, was said on 30 June to have the number of backers required to launch a challenge.

[29] Separate meetings to discuss the situation were held by Corbyn and Watson with UNITE trade union leader Len McCluskey on 5 July.

[30] Following the sacking of Hilary Benn, and the vote of no confidence in Corbyn's leadership, over 100,000 new members were reported to have joined the Labour Party by 8 July, taking membership numbers above 500,000.

[32][33] Corbyn challenged the rebels to stand against him,[34] and it was reported that Eagle had secured the support of at least the requisite number of nominations needed to launch a leadership bid.

[39][40] Additionally the NEC ruled that local Constituency Labour Parties should not hold members' meetings during the leadership election period.

[41] There was pressure before the nominations close on 20 July for one of the two challengers, either Smith or Eagle, to withdraw in order to unify the anti-Corbyn campaign.

[13][42] Smith explained that his decision to run for leader was partly because the future of the Labour party was at risk, stating that the "possibility of split is dangerously real".

[43] Andrew Rawnsley, chief political commentator for The Observer, described the leadership race as a crisis for Labour, which he saw as "fighting for its life."

The Collins Report also states: "The NEC should agree the detailed procedures for leadership elections including issues regarding registration, fees, and freeze dates".

[60][61] On 12 July the National Executive Committee ruled that as the incumbent, Corbyn would automatically be included on the ballot by an 18–14 vote.

[70] As the incumbent, Jeremy Corbyn, following an interpretation by the National Executive Committee of disputed Labour Party rules, was automatically included on the ballot.

In the past, some MPs have stated that they nominated only to ensure that a candidate (such as Corbyn) got onto the ballot paper;[71] however, it was (correctly) expected that Corbyn would face a single "unity candidate" after Angela Eagle and Owen Smith agreed that the person with fewer nominations from MPs/MEPs should step aside (which Eagle later did).

"[13][15] He explained that his decision to run for leader was partly because the future of the Labour party was at risk, stating that the "possibility of split is dangerously real".

[73] Corbyn applied to the court, and was accepted, to be the second defendant with his own legal team as Corbyn was "particularly affected and particularly interested in the proper construction of the rules" and that General Secretary of the Labour Party Iain McNicol was "being expected to vigorously defend a position which he regarded as incorrect prior to the NEC decision".

The polls below asked Labour Party local councillors across the country how they planned to vote in the leadership election.

In the aftermath of this event, Jeremy Corbyn was accused by his opponents of undermining the campaign to remain in the European Union, and faced a string of significant resignations from his Shadow Cabinet.

Smith announced his decision to stand down as an MP before the election, citing "personal and political reasons" in a letter to Corbyn.