france-420x0JULIAN LEE – Out in the cold … from next month Air France and KLM will make larger passengers pay an excess for a second seat Photo: Getty Images

Airlines are waging a war on flab. Two international airlines are proposing to force overweight passengers to buy a second seat if they are unable to squeeze into a single one.

From next month Air France and KLM will make its larger passengers pay 75 per cent of the cost of a second seat as well as the full price for the first.

The two airlines, which are part of the same group, cited safety reasons for the policy.

They go a step further than Australian airlines. But many American domestic airlines make those passengers who cannot fit into a 43 centimetre-wide seat with the armrests down and who cannot fasten their seat belt buy a second seat or get off the plane.

By law, Australian airlines can refuse to fly passengers under such circumstances.

But Qantas, Jetstar and Virgin Blue said that, where possible, they tried to accommodate overweight passengers by giving them an extra seat.

But to guarantee extra space, passengers should buy two seats.

A Jetstar spokesman said: ”We will do our best but we can’t give them a rolled-gold guarantee they will get an extra seat.”

A Virgin Blue spokeswoman said the difference between its guidelines and those of Air France was that it did not ”require people to book and pay for two seats”.

Air France and KLM were unavailable to clarify what constituted an overweight passenger or who decides if a passenger needs an extra seat.

The new policy is guaranteed to ignite a debate over whether airlines should discriminate against overweight passengers, not least in Australia, where 40 per cent of people are overweight and 21 per cent are obese.

Airlines argue the global obesity epidemic is costing them. In 2000 the American Journal of Preventive Medicine estimated US airlines were paying $275 million a year for the extra 1.1 billion litres of fuel required to lift larger Americans.

In 2008 a Canadian court forced its domestic airlines to comply with a one-person, one-fare policy that gave overweight passengers the right to an extra seat at no cost.

A spokesman for the Australian Human Rights Commission said it would encourage people suffering from obesity as a result of a medical condition to make a complaint if they were forced to buy two seats.