With opera lovers around the globe preparing to celebrate the 200th birthday of both composers, born a few months apart in 1813, La Scala has been accused of being unpatriotic at a time when Italy battles a recession some blame on austerity policies driven by Germany.

"La Scala puts Verdi in a corner, preferring the German," wrote il Giornale newspaper owned by former prime minister Silvio Berlusconi's family and known for its vitriolic attacks on German Chancellor Angela Merkel.

Corriere della Sera said there was unease in the orchestra pit over the choice of Wagner in Verdi's musical home and talked of "a blow to national pride in a moment of crisis."

La Scala general manager Stephane Lissner, a Frenchman, has dismissed the controversy as ridiculous.

"There are more serious problems than this Wagner-Verdi derby," he told reporters this week, pointing out that the theatre will stage six works by Wagner against eight by Verdi in the 2012/13 season.

Italian President Giorgio Napolitano was careful to clarify that he could not attend the gala opening because of pressing state business in Rome rather than deliver a deliberate snub. In a letter to the theatre, he called the row over Wagner "futile" and "pathetic".

Prime Minister Mario Monti, who replaced Berlusconi just over a year ago as Italy flirted with a Greek-style debt crisis, will be in attendance at one of the global social calendar's most glittering events along with five of his ministers.

For some, the debate reflects the storied rivalry between the two great composers and their supporters. When Verdi attended the Italian premiere of Lohengrin in 1871, he scribbled on a copy of the score: "Mediocre impression."

The romantic opera in three acts, generally considered one of Wagner's most accessible, centres on the doomed love between Lohengrin, a noble knight who cannot reveal his identity, and the daughter of the late ruler in the land of Brabant, Elsa.

Wagner specialist Daniel Barenboim conducts the opening night, with German tenor Jonas Kaufmann and German soprano Anja Harteros in the two lead roles.

The 234-year old theatre, which is navigating in troubled financial waters, is hoping its glamorous gala will help lure wider audiences and more sponsors. The performance will be broadcast live on television and in cinemas across Europe, Russia and Japan.

Public funds now only cover 40 percent of the La Scala budget and Lissner warned this week that without funds from the private sector the theatre would not be able survive. (Reporting By Silvia Aloisi)

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