More than 15,000 Protestants and Catholics rocked together past dark with Sir Elton John at a concert celebrating Northern Ireland's peace agreement.

John played for free at Wednesday evening's concert at Stormont, the Belfast negotiating venue where the historic multiparty accord was reached on Good Friday."I've looked forward to this for a long time. It's great to be back in the city," said John, steering clear of politics as he sang and bashed away at the keyboards for 2 1/2 hours.

Britain's Northern Ireland Secretary Mo Mowlam, tripping a bit on the only formality of the occasion, introduced the star as "Mister - oh, sorry - Sir Elton John."

Elton was knighted in February by Queen Elizabeth II for his 33-year singing career.

Profits from the sale of the $41 tickets will go toward improving facilities at Stormont, which will serve as the base for Northern Ireland's new cross-community government.