Despite the obvious hypocrisy, this is a comfort that just seems too good to give up for large companies that are brandishing their green credentials. Goldman Sachs, whose boss David Solomon was arguing how important a transition to a green economy was last week, bought two new corporate jets last year and is not expected to get rid of them anytime soon.

It is not just businesses failing to lead by example. Boris Johnson, who told world leaders at Cop26 to stop “quilting the earth in a suffocating blanket of Co2” and to “get real” about their responsibilities to the planet, flew back to London by private jet instead of taking the four-and-a-half hour train.

Downing Street defended the decision by saying he had “significant time constraints” which meant the train was not an option.

He was not alone. The conference is thought to have generated as much carbon dioxide as 4,200 Britons emit in a year, mainly due to the amount of private jets flying in. Lavish limousines were also spotted dropping wealthy delegates off at the conference before parking with their engines running.

Instead of turning their backs on elite travel as the earth warms, even more people have hopped aboard in recent years. CO2 emissions from private jets in Europe rose by nearly a third between 2005 and 2019, according to campaign group Transport & Environment, while data provider WingX said there has been a record number of private flights every month for the last six months.

Private jet use shot up 54pc in the first week of November compared to a year ago, showing that appetite for on-demand travel remains strong despite restrictions lifting. 

The pandemic has encouraged more people to fly private. Forbes’ latest annual world billionaires list shows that the rich have only got richer, with almost 90pc of the world’s billionaires wealthier than they were a year ago.