Dubai, Jan 5 (DPA) Thousands of people craned their necks Monday evening in Dubai to watch fireworks shoot from the sides of the world's tallest building, now called the Burj Khalifa, after United Arab Emirates (UAE) President Sheikh Khalifa bin Zayed al-Nahyan.

The tower had hitherto been called the Burj Dubai, but after a few brief remarks, Dubai's ruler, Sheikh Mohammed bin Rashid, pulled aside a curtain covering a plaque commemorating the inauguration of the Sheikh Khalifa bin Zayed al-Nahyan Tower.

In a celebration more in keeping with the culture of the Emirates' conservative rulers than the freewheeling expatriates who have flocked to Dubai looking for a piece of the credit-fed gold rush in recent years, the event began with children singing as Sheikh Mohammed entered.

Men performed a traditional sword dance while others glided into the ceremony on parachutes emblazoned with the UAE flag and its rulers' images. A similarly festooned hot-air balloon floated quietly into the night air.

As an orchestra played, a video screen proclaimed the building's height after years of mystery: 828 metres, a full 319 metres taller than the Taipei 101 tower, formerly the world's tallest building.

Only at the climax was the UAE's more recent reputation for razzmatazz on display: A spectacular, synchronised, light, fountain and fireworks show greeted the climax, with fireworks shooting off the sides of the building.

Sheikh Khalifa, the ruler of the neighbouring city-state of Abu Dhabi, the UAE capital, stayed close by Sheikh Mohammed's side throughout the ceremony.

Seated next to his cousin, Sheikh Mohammed at one point appeared to have a tear in his eye as he watched what should have been an unqualified testament to his city-state's rise as a world financial centre.

It was Sheikh Khalifa, who Forbes magazine estimates is personally worth $19 billion, who made the decision to bail out Dubai last month, as creditors clamoured following state-owned giant Dubai World's November announcement it was seeking a freeze on payments on $59 billion of liabilities.

Like so much in Dubai, the tower was designed by a Briton, in this case architect Adrian Smith. And like so much in Dubai, the tower was built by migrant workers, many of them from South Asia.

They toiled 22 million hours over the course of 1,325 days, pouring 330,000 cubic metres of reinforced concrete and fitting 103,000 sq metres of sheet glass nearly a kilometer off the ground to produce 1,000 luxury residences, 160 swish hotel rooms, and 37 office floors with corporate suites.

And as with other mega-projects in the city-state, as the Dubai property market continues to fall, investors in the Burj Khalifa, the Emirates' pride, will be watching to see if the millions of square metres of new office and residential space will be filled.