Jeff Kenyon, who owns Welly's bar-restaurant in Puerto Portals, southwest of Palma, thinks the idea is terrible. "Taxing tourists? It's like treating tourists as the enemy when they are our best friends. I might just as well charge an entrance fee for letting people into my restaurant."

Mr Kenyon calls to his barman to calm a shrieking coffee machine, before he continues. "The authorities should put up a monument to the unknown tourist and lay flowers at it every day, instead of punishing them - that's killing the goose that lays the golden eggs."

Surely those who can afford to moor their smart boats at the Puerto Portals marina and lunch at Welly's, which Mr Kenyon has run for 15 years, wouldn't jib at an extra £6 on their holiday price to improve the beaches and the services they enjoy?

He added: "This island owes everything to tourism. If they want to raise money to improve the environment they should impose landing fees at the airport. Taxing tourists is too obvious, too clumsy. Do I make myself clear?" He does.

A left-wing alliance won regional elections last year, promising to divert some of the tourism revenues to clean beaches, demolish shoddy hotels and improve roads and water supplies stretched to breaking point by the annual 10 million holidaymakers.

The Balearics' government tourism spokesman, Pepe Negron, says: "Our aim is to improve tourist areas and protect our natural spaces for tourist use, and we want to do so through negotiation." He adds that no tax will be implemented before next year.

Every formula put forward so far - airport tax, hotel tax, water tax - has been shot down by the mighty tourism industry, which objects to the idea of paying for improvements to the environment. But Miquel Angel March of the green Baleares Ornithological Group says: "Surveys suggest overwhelming support for an eco-tax. Hotels and tour operators in Majorca make millions. This is the richest region of Spain.

"We're oversaturated in the summer. We must freeze the galloping increase in building, and consumption of water and energy."

Hoteliers say tourists pay enough already. "In every package holiday you pay taxes for water, airport, rubbish disposal, fuel and the rest," says the hoteliers' spokesman, Joan Antonio Fuster. "Of course we need the money, but why don't they get it from Madrid? We send to Madrid 300bn pesetas (about £1bn) a year more than we receive."

Mr March is unconvinced: "The tourist sector must pay for the damage it has caused. Our island is being destroyed and local government revenues aren't enough to put things right."

Further along the coast, in the beautiful Calvia region, Kate Mentink, the president of the European Citizens group, represents the interests of some 320,000 absent property owners. "We're very worried about this tax. Are my members visitors or residents? Will they be charged every trip, or once a year? It's very unclear."

Despite the confusion, she believes the authorities are determined to press ahead. "It's been boomtown here for years, and nothing lasts for ever," Ms Mentink says.