Whitehall officials used a government plane for a £50,000 sightseeing tour around the UK, it has been claimed.
The 700-mile round trip took place on Wednesday afternoon, with 12 officials from the Foreign, Commonwealth and Development Office said to have got on the Airbus A321 plane.
Setting of from Stansted at 1.30pm before heading north, its flight path reportedly included views of the Lake District and the spa town of Moffat on the Scottish Borders, where the aeroplane turned around and headed back.
But it has sparked a backlash after claims that the excursion was 'effectively a jolly' by one insider.
In a report by The Sun it was said alcohol was served on board and staff were given a red-carpet welcome when they arrived on the runway.
Labour’s Shadow Trade Secretary Emily Thornberry told the outlet: “This would be utterly disgraceful behaviour at the best of times, but in the middle of our country’s current crisis, it is shameful beyond words.”
The government has since said that the flight formed part of a necessary maintenance procedure, as the jet needed to be used within 45 days for legal and operating purposes.
Responding to a request from The Mirror, a spokesman from the Foreign, Commonwealth and Development Office said: “In order to comply with Airbus and aviation industry rules the aircraft was legally bound to operate a maintenance flight before September 4 or face significant additional storage costs.”
They added that a number of officials joined the flight to make sure that following a recent reconfiguration of the aircraft it would still meet ministerial requirements, confirming that usual catering for a flight was available.
Some have questioned whether this justified the length of the trip at 91 minutes, with one flight expert claiming such routine test flights should take no longer than 45 minutes.
The Airbus A321 is known for being a close copy of the other official UK Government plane, the RAF Voyager, sharing the same Union flag livery and 'United Kingdom' lettering.
It has been nicknamed "baby Boris Force One" for its relatively small size compared to the Prime Minister's primary aeroplane, with others within government simply calling it the "little plane".
It will be used next week to transport the new Prime Minister up to Balmoral Castle, where the Queen will officially swear in either Liz Truss or Rishi Sunak in a sharp break with tradition that sees the function typically performed at Buckingham Palace.