THE bloodstained King of Crete stumbles onstage and holds aloft the decapitated heads of Poseidon, Jesus, Buddha and the Prophet Muhammad. “The gods are dead!” he calls out to the audience.

German operagoers will not be seeing that scene or, indeed, any scene from one of Mozart’s most powerful works. For fear of Muslim anger, the bosses of the world-renowned Deutsche Oper in Berlin have cancelled performances of Mozart’s Idomeneo. The decision has unleashed a storm of disapproval from politicians and writers, who claim that Germany has fatally compromised the freedom of expression.

Wolfgang Schäuble, the German Interior Minister who is due to open a conference today on Islam and German society, said that the decision to cancel the opera was insane, laughable and unacceptable. Other politicians said it was irresponsible.

The decision comes at a time of acute sensitivity in Europe about offending Islam. Police units have been set up in several EU countries to study potential flashpoints. Pope Benedict XVI’s comment on Islam — contained in a wider speech on religion and responsibility — also triggered unrest.

Kirsten Harms, the director of the Deutsche Oper, received a police report advising her that “disturbances could not be excluded” during performances of the Mozart opera. She decided to replace the opera, due to play from November 5, with The Marriage of Figaro. A Deutsche Oper spokesman said yesterday that putting on Idomeneo would “represent an incalculable security risk for the theatre at present”. It was, therefore, in the interests of the public that the opera should not be performed.

The production of Idomeneo by Hans Neuenfels was only mildly controversial when it was first performed in 2003. The plot of the opera, first performed in 1781, centres on Idomeneo, the King of Crete, who is saved by Poseidon from dying in a storm. To repay the god of the sea, the King is obliged to sacrifice the first person that he sees on reaching safety. This turns out to be his son.

The opera, with the usual entanglements of love and jealousy, shows how the King tries to escape from his debt to Poseidon. In the end his sacrifice entails handing power to his son and the woman he loves. The epilogue, as conceived by Neuenfels, has the King coming onstage with a bag of cut-off heads. With great care he props them on chairs. The message is clear: the gods are dead and humans have to take over their own destiny.

“If the mere fear of Islamic protest leads to self-censorship, then the democratic principle of freedom of expression is directly threatened,” said Bernd Neumann, the cultural adviser of Angela Merkel, the German Chancellor. “Art and the media have the task of setting out contradictions and arguments that are going on within society.”

Peter Ramsauer, the head of the conservative Christian Social Union parliamentary faction, had stronger words: “It is an act of pure cowardice. We are opening ourselves up to cultural blackmail.”

Not all theatres are ready to make concessions. The respected English Theatre in Frankfurt is staging the European English-language premiere of The Last Virgin, by Tuvia Tenenbom, the provocative Israeli-American playwright, which makes fun of suicide bombers. Talks have been held with the police and sniffer dogs patrol the aisles before every performance. No bags are allowed into the auditorium. There has been no trouble, though the play — which mocks Arabs and Jews in equal measure — has drawn fierce criticism from German Jews.

“We should never capitulate,” Tenenbom told The Times yesterday. “What kind of message is this sending to the Arabs on the street? Frankly, it is a racist decision because it is tantamount to saying that all Arabs cannot wait to blow themselves up in Europe.”

Neuenfels, who was due to stage the Mozart work, could barely conceal his fury yesterday. The opera has not been performed in Berlin since May 2004, but was being revived in its original production to mark Mozart Year. “This undermines all social discussion — the point of my supposedly controversial finale is to open up all religions equally to question, to examine their responsibility.” Some dramatists believe that the cancellation of the opera will become part of a pattern, with theatres across Europe quietly tidying up their repertoires to take out potentially offensive material.

Christoph Hegemann, of the Berlin Volksbühne (People’s Theatre), said: “The Goethe Institute (the equivalent of the British Council) and the whole business of cultural exchange has failed to create a protected sub-universe between the worldly and the religious.” As a result, religious leaders were unable to distinguish between art, social discourse and an attack on their faith.

Tenenbom said: “This self-censorship shouldn’t be happening anywhere, but least of all in Germany. This is where the Nazis burnt books. If you cancel performances because you’re scared, then you’re burning your own books on behalf of the fanatics. You don’t get crazier than that.”

Making a song and dance

Rameau’s 1733 Hippolyte et Aricie disregarded the rules of French opera. Factions it created fought in the press, and the street, throughout the 1730s

Times Recommends

• The Japanese Prime Minister is doomed: or is he?
• Brighton company 'involved in cyber attack'
• The art of survival: it's all in the mind