During the first intermission in the opening night production of "Tristan and Isolde," Chancellor Angela Merkel was said to have suffered a dizzy spell in the opera house restaurant, according to an online report in the "Bild" newspaper, slipping off her chair to the floor.

The tabloid reported that it took the chancellor two minutes to recover, helped by fellow guests who included Bundestag President Norbert Lammert and Culture Minister Monika Grütters.

A short time later, however, deputy government spokesman Georg Streiter denied the report, offering no further comment. "Bild" later reported that a broken chair may have been to blame for the fall.

Merkel left at the end of the five-hour, three-act opera, saying only that she had liked the production.

The annual Bayreuth Festival is one of Germany's cultural highlights, and Merkel has attended regularly with her husband Joachim Sauer.

New production, new music director

Wagner's great-granddaughter, the 37-year-old Katharina Wagner, runs the month-long summer music festival.

Her new production of "Tristan and Isolde" was warmly received at its premiere on Saturday. In her dark and pessimistic staging of the work, the first act was set as a maze of dark staircases. Tristan is the captain of a ship carrying the Irish princess Isolde as a trophy bride for Tristan's King Marke in Cornwall.

The second act took place in what appeared to be a madhouse, while the third act portrayed the delirium of the dying Tristan.

After the show, US tenor Stephen Gould received loud applause for his portrayal of Tristan.

According to comments from audience members, however, there wasn't such a warm reception for new music director Christian Thielemann. His role as the first independent music director for the festival was revealed in June, when his personal parking place was revealed. A Bayreuth spokesperson later confirmed the rumours of his appointment.

Thielemann's formal duties were to be announced on Saturday. He was already the festival's music adviser, but the new role is unprecedented at Bayreuth. Previously, a Wagner family representative has taken on the role of music director - starting with Wagner's widow Cosima and continuing with Wieland and Wolfgang Wagner, his grandsons.

This year marks the 150th anniversary since "Tristan and Isolde" had its world premiere. Katharina Wagner's interpretation is only the 11th production of the work at the Bayreuth Festival.

A ticket for Bayreuth is very hard to come by, with the waiting list as long as 14 years for some productions.

The festival, with its 30 performances of seven different operas, continues until August 28.

jm/cmk (AFP, Reuters, dpa)