A video showing an Emirates flight attendant pouring a glass of champagne back into the bottle has caused a stir after it was posted online.

The footage was recorded by Russian passenger Yevgeny Kaymov who unknowingly filmed the incident on a business class flight to Dubai.

He posted the video to his Instagram account, tagging the airline in his caption. Kaymov wrote: “I accidentally filmed this video, and didn't even notice this moment at the time, pouring unfinished champagne back into the bottle.

“Is that normal practice Emirates?”

The film appears to show a tray of untouched glasses of champagne. The carrier offers the sparkling wine to first and business class passengers after they board the aircraft.

But although the video has cause a firestorm on social media, not everyone thinks the flight attendant is in the wrong. On a Reddit thread about the video, which has over 3,000 comments a contributor said: “I'm a flight attendant - the attendant is probably pouring the unused champagne back in the bottle before take-off to then dispose of once the plane takes off.

“We're not allowed to pour things out while we're on the ground. I bet they're pouring it all back in the bottle so they can then pour it out at cruising instead of dumping it all in the trash can making it all soggy.”

Other commenters pointed out that the stewardess may not have been reusing it or saving it for herself as the beverage would soon lose its fizz. One said: “It's champagne. It's carbonated. You literally cannot reuse it, it will be flat.”

The Independent's anonymous cabin crew columnist “Brad Bernoulli” weighed in with his own assessment. “Until airlines can adequately stock their planes, flight attendants will always look for ways to conserve popular items that often run out to avoid making excuses about why they are out. Frontline employees bear the brunt of many angry customer reactions, and if saving a few glasses of bubbly makes the 16-hour flight go smoother, the airline shouldn't expect anything less.”

He disagreed with the Reddit commenter, saying that there was no reason he could think of which would prevent her from pouring the liquid away normally. “We can't pour hot liquids out when we are parked at the gate, but I get rid of them by putting it in the toilet and flushing.” He added: “I think she was conserving it. Emirates probably has the best ability to cater adequately as they literally don't care about costs, which is why I found it strange she was pouring it back in the bottle, but if it was a popular drink, then I would have done the same thing rather than waste it.”

However, the airline itself has been less sympathetic. It told The Independent: “Emirates always strives to provide the top quality service. Actions recorded on this video do not comply with our quality standards. We are currently investigating the incident.”