The anonymous letter, purportedly the work of five staffers who work for other Labor MPs, was posted online on Monday evening, alleging a destructive and intimidating culture in Albanese’s office.

The letter, which disappeared late Monday, only to reappear on Tuesday on a different website, was widely distributed among Labor staffers, parliamentarians and journalists.

The ABC is aware that at least one foreign embassy saw it online.

Internal tensions have bubbled over in recent weeks, with Albanese’s policy direction and leadership coming under closer scrutiny.

Last week, two Labor frontbenchers almost came to blows inside Shadow Cabinet as Joel Fitzgibbon and Mark Dreyfus squabbled over climate policy.

The following day, Fitzgibbon quit the frontbench, citing a desire to speak more freely about Labor’s stance on emission reductions. He also wants Labor to change its policies to appeal to blue collar workers and regional Australia.

Asked about the letter, Albanese refused to comment on the details.

“It’s fake,” he said repeatedly.

Albanese went on to defend the culture within his office.

“It’s a very good office. I have an outstanding office,” he said.

But the ABC has confirmed Albanese’s chief of staff Tim Gartrell recently used an all-staff meeting to call for greater discipline and a disbanding of “cliques” within the office.

It’s understood an internal messaging system used inside the Opposition Leader’s office, called Slack, was rebooted, deleting old messages.

Several Labor sources told the ABC the letter was consistent with their experience with Albanese’s office.

The dossier includes an email in which sexist and derogatory language was purportedly used by a senior staff member to describe a woman.

The ABC has asked Albanese’s office if this email is also fake. An answer is yet to be received.

Shadow Treasurer Jim Chalmers confirmed he was aware of the matter.

“I’m aware that there has been an issue raised, obviously it’ll need to be dealt with in one way or another,” Chalmers said.