A pair of US lawmakers have threatened legal action against US Attorney General Pam Bondi, after her deadline to release all government files related to the late convicted sex offender Jeffrey Epstein was met only in part.

The release of the Department of Justice (DoJ) documents was highly anticipated but in the end, only a portion of the available material was made public.

A leading campaigner on the issue, Republican congressman Thomas Massie, said he could try to bring contempt proceedings against the attorney general as a result.

The DoJ insists it is complying with its legal obligations, and Bondi herself has said she is part of 'the most transparent administration in American history'.

The phrase 'Epstein files' refers to the trove of information that was amassed by the US justice department during its two criminal investigations into Epstein.

A law that compelled the release of the full trove was signed by US President Donald Trump in November, after pressure from his supporters and members of his own Republican Party. Friday was the deadline for the release of the material.

Although some material was released, there were many redactions and other information was withheld - which angered Massie and his allies, as well as survivors of Epstein's abuse. Trump himself is yet to comment.

The DoJ has said that more material will follow in the coming weeks.

But speaking to CBS programme Face the Nation on Sunday, Massie suggested that the justice department was 'flouting the spirit and the letter of the law'.

He went on to say: 'The quickest way, and I think most expeditious way, to get justice for these victims is to bring inherent contempt against Pam Bondi, and that doesn't require going through the courts.'

Inherent contempt is a little-used legal recourse that can be used by either the Senate or House - the upper and lower chambers of Congress respectively - which has not been invoked for nearly a century.

Massie added that 'Ro Khanna and I are talking about and drafting that right now', referring to a Democratic congressman who has also been prominent in the campaign for the release of the full Epstein files.

Bondi's deputy Todd Blanche was defiant during an interview with another broadcaster on Sunday.

Asked by the Meet the Press programme on NBC News whether he took threats from Congress members seriously, the deputy attorney general said: 'Not even a little bit. Bring it on. We are doing everything we're supposed to be doing to comply with the statute.'

Blanche pointed to the magnitude of the task. 'You're talking about a million or so pages of documents. Virtually all of them contain victim information.'

He continued: 'And if by complying with the statute we don't produce everything on Friday, we produce things next week and the week after, that's still compliance with the statute.'

Speaking to the same programme, another member of Khanna's party, Democratic Senator Tim Kaine, said contempt or impeachment efforts would be 'premature'.