"Undress for the Opera" has the backing of former Blur frontman Damon Albarn, whose operatic work "Dr. Dee" was part of the ENO's 2011/12 season and attracted 60 percent of new ticket buyers.

Albarn, one of the biggest names in British pop, hesitated to call Dr. Dee an opera, reflecting the suspicion with which the art form is viewed by many.

"I don't really know what to call it," Albarn told reporters at the ENO's Coliseum theatre in central London.

"I struggle with the word opera because it's quite clear that I'm sort of swimming in deep water when I ever mention that word, so I try and avoid it."

American-born film director Terry Gilliam, who directed Berlioz's "The Damnation of Faust" at the ENO last year and is planning to work with the company again, also backed the new drive to find opera converts.

"I suppose I'm trying to bring in people like myself who didn't go to opera when they were younger, because I thought it was just for a bunch of old farts and a lot of bourgeoisie and people in dinner jackets," he said in a filmed interview.

"It was an art for the rich and the successful and the almost dead."

The ENO has helped to change that perception, aided by the fact that it performs operas in English and is housed in an old music hall which had "none of the pretensions of an opera house."

Gilliam conceded that opera was expensive - a ticket in the stalls at the ENO costs between 83 and 95 pounds, and at the nearby Royal Opera House up to 250 pounds for a coveted seat to see a performance from German composer Richard Wagner's "Ring" cycle.

Undress for the Opera offered the best seats for 25 pounds each, including a pre-performance introduction, at four designated nights during the 2012/13 season.

Organisers said 100 seats would be made available under the favourable terms to Wolfgang Amadeus Mozart's "Don Giovanni" on November 15, Giuseppe Verdi's "La Traviata" on February 7, 2013, the world premiere of "The Sunken Garden", by Dutch composer Michel van der Aa on April 18 and "The Perfect American" by U.S. composer Philip Glass on June 13.

John Berry, the ENO's artistic director, said he wanted 40 percent of his audience to be younger than 44 years old within the next 18 months from 30 percent now.

"Young people like informality and we want to say that you don't need ties or tiaras to enjoy opera at ENO," Berry said.

Asked why he was backing the project, Albarn replied: "I'm quite clearly not someone who had any form of opera education and I've done it entirely instinctively and the fact that the English National Opera is prepared to encourage that is just a great sign of its health.

"At some point I hope that I can deliver something to you (the ENO) that really ticks every single box but doesn't compromise where I come from as well, and if you can do that then you will, truly, get a new audience in here." (Reporting by Mike Collett-White, editing by Paul Casciato)

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