The US Justice Department has said it had uncovered efforts to obstruct its investigation into the discovery of classified documents at former President Donald Trump's Florida estate, saying government records were likely concealed and removed from a storage room at the property.

The assertion was made in a court filing on Tuesday night that lays out the most detailed chronology to date of interactions between Justice Department officials and Trump representatives over the presence of the documents at Mar-a-Lago.

The department says Trump's lawyers told them in June that all the records that had come from the White House were stored in one location a Mar-a-Lago storage room and that there were no other records stored in any private office space or other location at the Premises and that all available boxes were searched .

In their search earlier this month, however, agents found classified documents both in the storage room as well as in the former president's office -- including three classified documents found not in boxes, but in office desks.

Tuesday night's filing also included a photo showing the cover pages of classified documents and some marked as TOP SECRET/SCI with a bright yellow border laying on a carpet at Mar-a-Lago alongside a box filled with framed pcitures, including a Time Magazine cover.

The Justice Department was responding to a request from the Trump legal team for a special master to review the documents seized during the August 8 search of Mar-a-Lago. US District Judge Aileen Cannon is set to hear arguments on the matter.

Trump's lawyers last week asked for the appointment of a special master who'd be tasked with reviewing the records taken and setting aside documents protected by claims of legal privilege.

Cannon on Saturday said it was her preliminary intent to appoint such a person but also gave the Justice Department an opportunity to respond.

The department on Monday said it had already completed its review of potentially privileged documents and identified a limited set of materials that potentially contain attorney-client privileged information .

In a separate development, the Trump legal team has grown with the addition of another attorney. Chris Kise, Florida's former solicitor general, has joined the team of lawyers representing Trump, according to two people familiar with the matter who were not authorised to discuss the move by name and spoke on condition of anonymity. Kise did not return messages seeking comment.