"This incident never happened. As there is no record of it, no complained that was filed either in London, New Delhi or on-board the flight. No cabin crew or even the other passengers on the flight are even aware of such an incident and no one has come forward to complaint even now," a senior Air India official in New Delhi told IANS.

"It is clearly a hoax. This all started with a picture appearing on Twitter. We are investigating the matter, as to who has placed the picture, and what is the claim of that person," the official added.

The airline has warned that if the incident actually turns out to be a hoax, which it is certain-off, then it may also resort to legal action.

"Our food is catered by the India's best hospitality chain the Taj. The Taj Stats delivers one of the finest and award winning in-flight food. This is all being done to tarnish our image," the official added.

According to the industry sources, the incident came to light when a picture was posted on Twitter, that showed what seemed to be a small 'lizard' on the food tray of a passenger. The photo has ever since gone viral.

Other sources claim that the incident took place on AI-111, a Boeing 787 Dreamliner that took-off on Thursday from New Delhi's IGI airport for London.

During a 10-hour-long flight, the airline serves an unlimited number of snacks and two main courses depending on the time of operations.