Investigation into leaked Labour anti-semitism report to reveal its findings by mid-July
Keir Starmer ordered an investigation into the report.
An independent inquiry into a leaked report on Labour anti-semitism will report back within three months.
The terms of reference for the probe were agreed at a meeting of the party's ruling National Executive Committee.
Sir Keir Starmer and Labour deputy leader Angela Rayner called for the investigation after the 860-page dossieir was leaked almost two weeks ago.
The report was authorised by senior Labour officials close to former leader Jeremy Corbyn.
It revealed an extensive cache of WhatsApp messages between senior party officials - including former general secretary Lord McNicol - in which they made derogatory remarks about Mr Corbyn, his aides and frontbench allies.
The personal details of whistleblowers and the alleged victims of anti-semitism were also contained in the unredacted document.
Supporters of Mr Corbyn claimed its contents proved those on the right of the party had undermined his attempts to tackle anti-Jewish racism as well as sabotaged Labour's 2017 general election campaign.
In a statement issued on Thursday, a spokesperson for the Labour Party said: "The National Executive Committee has today agreed the terms of reference for the independent investigation into the circumstances, contents and release of an internal report.
"The NEC will meet again in due course to agree the individuals who will be appointed to lead the investigation."
A spokesperson for pro-Corbyn campaign group Momentum said Sir Keir had told the meeting that anyone found to have broken party rules would face disciplinary action.
"Ordinary members would rightly face disciplinary action if they engaged in such activity, senior staff members should be held to even higher standards," they said.