The Department for Energy and Climate Change spent more than £300,000 flying ministers around the UK, new figures have revealed.
According to the Daily Telegraph, the department spent £148,000 of taxpayers' money on 668 internal flights last year and an additional £163,000 on 1,000 domestic flights.
Green MP Caroline Lucas told the Daily Mail: "I find it hard to believe that trains weren't an option on at least some of these routes.
"Given the impact of carbon emissions from aviation, it's disappointing that the department isn't showing more leadership."
A breakdown of the flights showed mostly trips of more than 400 miles between London and Scotland, but there were also shorter journeys, including Aberdeen to Wick Airport in the far north of Scotland, which are only 200 miles apart by road.
The figures revealed that the Home Office spent the most money on flights, spending £700,012 on 7,200 flights.
While the Department for Environment, Food and Rural Affairs took just 219 domestic flights at cost of £37,445.
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