Acting Labour leader Harriet Harman has asked to speak to all four leadership candidates amid growing concerns the vote could have been infiltrated by opponents.
The private meeting is expected to focus on checking the process to make sure there are no votes made by those who are looking to skew the result.
“The meeting will be a chance for candidates and teams to raise their concerns about the process and come to a solution,” a Labour party spokesperson said.
The Labour party has allowed the public to register for the leadership vote by pledging just £3. However, speculation has emerged over the last few weeks that those who do not share Labour's “values” and “aims” are trying to infiltrate the party to skew the election result.
The meeting comes after Andy Burnham, who is second in the polls to Jeremy Corbyn, raised the alarm over “several thousand” possible Conservative infiltrators.
Earlier this month 1,200 people were banned from taking part because they support rival parties, including film director Ken Loach, journalist Toby Young and Conservative MP Tim Loughton.
Yet, last week it emerged that genuine Labour party supporters had been blocked from voting by the party. The Independent has also reported there are new fears from the Labour party over British National Party supporters trying to vote.
Jeremy Corbyn, however, rejected the infiltration claims as "nonsense" at BBC Radio 5 live hustings in Stevenage.
It also comes after further controversy, as leaked files, seen by the Guardian, show how a Labour committee ignored the advice of lawyers on verifying new registries.
Party lawyers had pushed for an extra stage of verification, which would have asked people known to have voted for other political parties to confirm again they support Labour party values, writing to explain why they are now supporting Labour.
But, the Labour committee voted against this measure, which the lawyers said could make the party more likely to face a legal challenge by unsuccessful candidates after the vote.