President George W. Bush and first lady Laura Bush have joined actors and musicians in a concert to mark the anniversary of the 11 September attacks in New York.

The concert, in the Kennedy Center, featured performances by Placido Domingo, Gloria Estefan, Aretha Franklin, Al Green and Alan Jackson.

Enrique Iglesias sang at the event to be shown on TV

The two-hour event, called Concert for America, was recorded for NBC and will be shown across America on Wednesday.

"Today we mourn the lost, honour the living and celebrate the character of our country and the creativity of our people," the president told the audience, which also included Secretary of State Colin Powell.

Dramatic readings

"Music seems to say and touch people in a way that no other form of expression can," National Symphony Orchestra music director Leonard Slatkin said before the performance.

Actors James Earl Jones and Angela Bassett did dramatic readings.

Singer Chris Isaak called the tribute a ceremony, like putting flowers on a grave.

"I don't know what music does or what exactly singing, or getting people together does," he told reporters before the show. "But it's something we do, and I can't think of much else we could do."

Stars from the world of stage and screen are also taking part in a number of events in the city to mark the anniversary of the attacks.

A theatre marathon in New York is being held, starring Sarah Jessica Parker, Matthew Broderick and Calista Flockhart among others.

Roots

The three-day theatre event to mark the anniversary, called the Brave New World Arts and Theater Marathon, features 50 new plays, songs and multi-media pieces written and composed for three evenings and one matinee performance.

The aim of the event is to unite and encourage American theatre to explore the roots of terrorism and address the changes in the world since the atrocities.

Money raised from the shows at New York's Town Hall will be donated to the New York Children's Foundation, dedicated to children affected by the attacks.

Sopranos star Edie Falco is taking part in the marathon

There will also be a special performance of The 24 Hour Plays, a concept which sees six short plays written, cast and performed in one day.

Others donating their time for the event include Billy Crudup, Marisa Tomei and Rosie Perez at New York's Minetta Lane Theater.

Meanwhile, Broadway has remained divided about how to mark the anniversary.

Producers of nine shows, including Hairspray and The Producers, have decided the show must go on with performances going ahead on Wednesday.

Lifestyle

But 13 other shows have cancelled the day's performances as a mark of respect.

However, all theatres will dim their marquee lights for one minute at 2000 (0100 BST), a custom usually reserved for the passing of a Broadway star.

Jed Bernstein, president of the League of American Theatres said there had been attempts to reach a joint decision about how to respond to the anniversary but no agreement could be reached.

"Basically there were two schools of thought: stay open to show that our lifestyle has endured the terrorist threat and shut down out of respect for the victims.

"Both are legitimate and it soon became obvious that the only solution was to let each individual theatre decide what they thought was best," he added.