The British Airways apologised to the passengers for the delay. (File photo)

A London-bound British Airways flight with 300 passengers onboard aborted take-off at the last minute in Mumbai on Saturday due to an engine snag, delaying the departure by more than five hours, a source told news agency PTI.

"British Airways flight BA 134 was forced to reject take off for London at Chhatrapati Shivaji International Airport here as the aircraft engine developed a snag. The aircraft came back to the bay and all the passengers escaped unhurt," said the source.

The airline's spokesperson, in a brief statement, said the aircraft returned after an indication of a "minor technical" issue, without giving details such as the number of passengers on board or even the flight number.

"The aircraft returned to stand after an indication of a minor technical issue, where it was met by the emergency services as a precaution. A team of highly skilled engineers inspected the aircraft and confirmed it is safe to fly," the spokesperson said.

The airline apologised to the passengers for the delay and they are currently on their way to Heathrow, he said.

Bharat Vasani, partner of leading law firm Cyril Amarchand Mangaldas, tweeted: "More than 300 passengers are stuck inside British Airways Mumbai-London flight BA 134 since 11.30 am. Commander aborted take-off due to a problem with the left engine of Boeing 787 aircraft. Aircraft stopped with violent jerks. No one allowed to disembark for last 2 hours."

"The flight finally took off at around 5 pm," Mr Vasani tweeted.