FOREIGN Secretary Liz Truss took a £500,000 trip to Australia on the government's private jet.

The plush plane dubbed the 'union jet' due to its Union Jack paint job, was used to transport Ms Truss from London to Sydney on January 18, and back again five days later.

Campaigners have criticised the decision to take the private flight, and questioned why the Foreign Secretary could not have travelled on commercial airline Qantas, which would have seen her arrive earlier and cost as much as £490,000 less.

According to the Independent, the private jet stopped twice on the 22,000 mile trip with a 90-minute stop at Dubai and another at Kuala Lumpur.

Ms Truss touched down in Sydney shortly after midnight on Thursday January 20.

If she had taken one of the daily Qantas flights instead, she could have arrived five hours earlier. 

The private government Airbus A321 is used by ministers and members of the royal family, and comes with a VIP interior – including lie-flat beds.

The mission to Australia and back burnt an estimated 150 tonnes of fuel and generated nearly 500 tonnes of CO2.

An aviation source told the Independent the cost of operating Ms Truss’s trip would have been “at least £500,000”, while the most expensive business-class tickets which also offers lie-flat beds would have been cost just over £7,700.

It si reported that Foreign Office sources claim Ms Truss needed to take the luxury plane for security reasons, as other passengers may have overheard confidential discussions about goevrnment business.

It is also claimed Ms Truss needed to have flexibility to set off to another destination in the event of a crisis in other regions, such as Ukraine. 

Labour has criticised the decision, with deputy Angela Rayner saying it was a "disgusting" waste of money

She said: "Liz Truss shows the public exactly quite how little respect this Conservative Government has for taxpayers' money with her ridiculous waste of half a million pounds on a private jet trip.

"This Government is brazen in its disregard for upholding decency.

"It is obscene that Government Ministers are jet setting yet are hiking taxes and refusing to do anything to help working families when they are feeling the pinch of the cost of living crisis.

"Tories waste disgusting amounts of public money on their own vanity and comfort, Labour wants to see families see a cut to energy bills - that is the difference."

The SNP's envronment spokeswoman Deidre Brock described the flight as a "grotesque misuse of taxpayers' money" and referred to Ms Truss as "Lavish Liz".

She said: "Taxpayers will be appalled that the Tory Foreign Secretary has reportedly wasted over half a million pounds of our money on a luxury private jet trip - and emitted tonnes of unnecessary carbon emissions during a climate crisis.

"Ms Truss has a history of frittering away public funds. Only recently, she was criticised for splashing out over a thousand pounds on a single lunch, which saw her quaffing high-end wines in a Mayfair private members club owned by a Tory donor.

"With a record like this, Lavish Liz will make a fitting successor to Boris Johnson."

Anna Hughes, director of Flight Free UK said: “ Liz Truss has consistently demonstrated her lack of understanding about the action that we all need to take to address the climate crisis, and this is no exception.

“Flying to Australia and back on a chartered jet is shockingly privileged and an outrageous source of emissions in the current climate emergency.”

A Foreign Office spokesman said: “It’s necessary for the Foreign Secretary to travel abroad to pursue UK interests around security, trade and technology, as she did during this visit to Australia.

“Travelling this way allows Ministers to have private discussions on sensitive security matters and flexibility to respond to rapidly changing global events.

“This trip used government transport and was fully within rules.”