Nearly 500 passengers arrived in Singapore Tuesday in a A380 relief jet after their original flight from London to Singapore was forced to land in capital Baku due to a loss in cabin pressure.

"The root cause of the incident is being investigated and a team of specialists from Airbus will be assisting," an airline spokesman said in a statement.

"We are focusing on a door on the main deck that appears to have suffered a leak, leading to the change in cabin pressure," he said.

"A replacement door will be fitted to the aircraft in Baku before it returns to Singapore for a more thorough inspection."

Passengers had spoken of noise coming from one door as the aircraft came in to land in the central Asian republic.

The A380 is the world's largest commercial aircraft and Singapore Airlines was its debut customer in 2007.

Sean Lee, the Asia spokesman for Airbus, told AFP Wednesday that the European manufacturer is "participating fully in the investigation to determine the cause of this incident".

"I confirm that we have a team of specialists travelling to Baku. At this time we cannot confirm the root cause of the incident," he said.

There are 119 Airbus A380s in operation globally, according to latest data from the company.

Singapore Airlines currently has a fleet of 19 A380s, with five others on order. It uses the planes for flights from Singapore to various destinations including Frankfurt, Hong Kong, London and Los Angeles.