Labour says it has received the draft findings of the equality watchdog's report into anti-Semitism in the party.
It said Sir Keir Starmer would not be commenting until the final report was published later this year.
But it stressed it was committed to enacting all the Equality and Human Rights Commission's recommendations.
The watchdog began the unprecedented inquiry in May 2019 following criticism of the party's handling of allegations against members and activists.
The EHRC has been looking at the party's much-criticised complaints procedures and the extent to which its internal culture under Jeremy Corbyn's leadership allowed anti-Semitism to grow since 2015.
Labour and other organisations which may be facing criticism have 28 days in which to respond to the draft report's conclusions as part of the process, meaning its publication is unlikely before September.
The party said Sir Keir and his deputy Angela Rayner, who were elected in April, would not be commenting before then but were clear that eradicating anti-Semitism and restoring trust with the Jewish community was a priority.
"The draft report has been shared with the Labour Party as part of a process afforded to us prior to the report's publication," the party said.
"It is sent in confidence by the EHRC, so until that process is completed, it would be inappropriate to comment on any of the contents of the draft report.
"We are committed to cooperating fully with the Commission's investigation and implementing its recommendations when the final report is published."
The watchdog has been looking into whether Labour "unlawfully discriminated against, harassed or victimised people because they are Jewish".
In particular, it said it would determine whether unlawful acts have been committed by the party and its employees and whether the party responded to complaints of unlawful acts in a lawful, efficient and effective manner.
The inquiry was set up following complaints by the Campaign Against Anti-Semitism and the Jewish Labour Movement (JLM).
The Campaign Against Anti-Semitism said the new Labour leader must be judged by his actions and urged him to set out a clear timeline for overhauling the party's disciplinary procedures.
"The party must be forever changed after this episode so this can never happen again," it said. "Those responsible must be held to account if Sir Keir Starmer is to tear anti-Semitism 'out by its roots', as he has promised.
"The EHRC's report is a pivotal moment in this corrective process."
The JLM, which is officially affiliated to the Labour Party, said the report had to be the catalyst for an end to the "casual atmosphere of denial" in the party about anti-Semitism.
"As a third-party to the investigation, we have not had sight of the final report," it said.
"We hope that when it is published, it will provide the kind of impartial and independent scrutiny required to force the party to comply with its duties under the Equality Act and toward our members."