One of the highlights of the classical music season, the Bayreuth Festival, which celebrates the music of Richard Wagner, may be played out in darkness this year. The scenery may also be shifted by members of the Wagner family because workers are fed up with being paid little more than €4 (£3.40) an hour.

It would be difficult to imagine a more embarrassing start to the festival, which is due to begin on July 25 with a production of Tristan and Isolde. The festival attracts Wagnerians such as Angela Merkel, the German Chancellor, and José Manuel Barroso, the President of the European Commission.

The festival is to be under the direction of Katharina Wagner, 31, and Eva Pasquier-Wagner, 63, for the first time. The half-sisters ended decades of family feuding and are committed to confronting the taboo of the Nazi era — Wagner was Hitler’s favourite composer — by staging an abbreviated children’s version of one of the operas and by broadcasting the performances live. The Greek President, half of the German Cabinet, a gaggle of Eastern European ministers and film stars have been jostling for tickets to witness the musical revolution.

It seems that 60 stagehands and lighting engineers, and 100 freelance workers, may put the revolution on hold, however. Unless a deal is struck in negotiations on Monday there will be a strike on Wagner’s fabled Green Hill above the Bavarian town of Bayreuth. “At the moment a strike seems likely,” Peter Emmerich, the festival spokesman, said. Barbara Schneider, a union activist who wants the Wagners to pay workers the same as other orchestras and opera houses, said that the contracts negotiated by Wolfgang Wagner, the outgoing director and father of Katharina and Eva, were of dubious legality.

“If you work out what is really paid to the freelance stagehands, taking into account the time they put in during the festival, then you come out at about €4 an hour. And if that entails the two directors shoving the scenery in themselves, then so be it,” she said.

The workers at the opera house work long hours, often through the night during the festival month, but they accepted the arrangement because of their respect for the previous director. Mr Wagner, 89, paid non-union rates but set aside two nights out of the 30-night festival for trade unionists. They had to pay for the tickets but many were able to enhance their earnings by selling their tickets on — Wagner fans have been known to pay thousands of pounds for tickets.

This perk exists under the new management but the Verdi union wants to put pay on a more professional footing.

“It really shouldn’t be a problem to pay stage staff an acceptable wage and pass on the costs by raising ticket prices,” said Fritz Schösser of the Bavarian division of the German Trade Union Federation.

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