Overweight passengers who cannot squeeze into a single plane seat are to be charged double to fly with Air France.

People who cannot fit into a standard seat will be asked to pay for two seats, or not be allowed on board for "safety reasons", according to the airline.

Air France spokeswoman Monique Matze said: "We have to make sure that the backrest can move freely up and down and that all passengers are securely fastened with a safety belt.

"The charge will only apply on flights that are fully booked. They will get their money back on flights where spaces are available."

The airline intends to charge passengers 75% of the cost of the second seat on top of the full price for the first.

Air France was ordered to pay £5,000 damages in 2007 for "humiliation" to a 27-stone passenger at an airport check-in desk in New Delhi.

Frenchman Jean-Jacques Jauffret, 43, had his stomach measured by Air France staff before being told he needed to buy two seats.

Mr Jauffret claimed he was told: "People as fat as you need to buy two seats."

United Airlines introduced the same policy last year, making passengers with extra-wide bodies pay for an extra seat.

Air France's new charges will apply for people who book their tickets from February 1 for all flights from April 1.