The introduction of a 'fat tax' on obese passengers moved one step forward today with Ryanair announcing ways it could levy the charge.

The Irish airline has come up with four alternatives and is asking passengers to vote on which option is most acceptable.

In what is seen as a backdoor way to introduce the tax ("led by passenger demand" etc.,), Ryanair said that it would now consider how to charge the fat tax.

The move comes after more than 30,000 passengers voted in favour of charging excess weight fees for very large passengers in an online vote over the past two weeks, said a spokesman.

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A Times Online report on how Ryanair was maneouvering to bring in the tax last week attracted 42 comments, many in favour. And an Online poll attracted 590 votes - with two-thirds also in favour.

The Ryanair proposals are:

* Charge per kg over 130kg/20 stone (male) and 100kg/15 stone (females);

* Charge per inch for every waist inch over 45 inch (male) and 40 inch (female);

* Charge for every point in excess of 40 points on the Body Mass Index (+30 points is obese);

* Charge for a second seat if passengers’ waist touches both armrests simultaneously.

Ryanair spokesman Stephen McNamara said: “With passengers voting overwhelmingly for a ‘fat tax’ we are now asking them to suggest which format the charge should take.

"The above four points seem to us to be the simplest, fairest and administratively easiest to apply. In all cases we’ve limits at very high levels so that a ‘fat tax’ will only apply to those really large passengers who invade’ the space of the passengers sitting beside them."

Passengers can vote for their preference on www.ryanair.com until Monday April 27.

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