MOSCOW, June 14 - Russia declared the soccer World Cup open on Thursday at a glitzy ceremony in Moscow headlined by British pop star Robbie Williams and Russian soprano Aida Garifullina.

The 15-minute show produced by Russia's state Channel One broke from World Cup tradition, focusing on musical acts including a performance of Pyotr Tchaikovsky in front of full stands at the capital's main Luzhniki stadium.

Iker Casillas and Russian supermodel and philanthropist Natalia Vodianova brought the WorldCup trophy onto the pitch in a Louis Vuitton travel case.

Robbie Williams performed hits "Let Me Entertain You" and "Rock DJ" accompanied by dancers and freestylers.

He was joined in a duet by Garifullina, a soloist from the Vienna State Opera, who entered the pitch on a firebird, singing Williams' hit song "Angels".

The opening ceremony was due to be followed by a match between the host team and Saudi Arabia.