Boris Johnson has been accused of telling lies over the evacuation of Pen Farthing's animals from Afghanistan in the hours before the Allies withdrew from Kabul in the summer.
In what are reported to be leaked emails, Foreign Office officials appear to suggest the Prime Minister “authorised” their rescue, despite the Prime Minister previously saying it was “complete nonsense” that he had intervened.
Labour say that the new evidence shared with MPs showed Mr Johnson failed to tell the truth over how animals linked to the charity Nowzad had made their way to the UK during the Allied withdrawal from Kabul in the summer.
During the summer, Mr Farthing launched a high-profile campaign to get his staff and animals out of Afghanistan after the fall of Kabul, using a plane funded through donations.
The UK Government sponsored clearance for the charter flight, leading to allegations that animals had been prioritised over people in the exit effort.
The re-emergence of the row comes after a whistleblower leaked email exchanges to the Commons Foreign Affairs Committee, with MPs making them public on Wednesday.
The evidence shows an official in the private office of Lord Goldsmith – a joint Foreign Office and environment minister – told colleagues working on the evacuation on August 25 that “the PM has just authorised their staff and animals to be evacuated”, in reference to the charity Nowzad.
Written evidence submitted by a Foreign Office official showing an email from the Foreign Office says: "[Animal charity - name redacted] are a [details redacted] animal charity operating in Kabul and seeking to evacuation their [details redacted] members of staff (no animals).
"Equivalent charity Nowzad, run by an ex-Royal Marine, has received a lot of publicity and the PM has just authorised their staff and animals to be evacuated, [animal charity - name redacted] are hoping to be treated in the same capacity (granted LOTR)."
The email was handed to the committee by Raphael Marshall, who worked for the Foreign, Commonwealth and Development Office (FCDO) at the time, and has claimed the animals were evacuated following a direct instruction from the Prime Minister.
Mr Johnson has repeatedly denied the accusation, however, telling broadcasters on December 7 that insinuations of his involvement were “complete nonsense”.
On the same day in December, Lord Goldsmith told the House of Lords that the premier’s rebuttal was “entirely accurate”.
The Tory peer tweeted on Wednesday: “I did not authorise and do not support anything that would have put animals’ lives ahead of peoples’.
“My position, which I made clear publicly, was that the UK should prioritise evacuating people.
“I never discussed the Nowzad charity or their efforts to evacuate animals with the PM.”
But opposition parties said the email disclosure to MPs indicated the “Prime Minister has been caught out lying” and accused him of making the “wrong calls”.
A Downing Street spokesman said: “The Prime Minister had no role in authorising individual evacuations from Afghanistan during Op Pitting, including Nowzad staff and animals.
“At no point did the Prime Minister instruct staff to take any particular course of action on Nowzad.”
In a statement, Nowzad said: “As a charity, we had no oversight of any communication between any Government departments relating to who authorised the call forward of the Nowzad staff.”
It said only Mr Farthing, with his animals “in the cargo hold”, was able to leave Kabul in a chartered flight, with 67 Afghan staff and vets evacuated “by road to start new lives” in Britain.
The organisation said “no British military were put in harm’s way” and that the animal rescue occurred “after the British military had already ended Operation Pitting”.
