Started at the height of the economic boom and built by some 12,000 laborers, the world's tallest building will open on Monday in Dubai as the glitzy emirate seeks to rekindle optimism after its financial crisis.

Burj Dubai, whose opening has been delayed twice since construction began in 2004, will mark another milestone for the deeply indebted emirate with a penchant for seeking new records.

Dubai, one of seven members of the United Arab Emirates, gained a reputation for excess with the creation of man-made islands shaped like palms and an indoor ski slope in the desert.

With investor confidence in Dubai badly bruised by the emirate's announcement in November that it would seek a debt standstill for one of its largest conglomerates, the Burj Dubai is seen as a positive start to the year after a bleak 2009.

The project has been scrutinized by human rights groups, who have objected to its treatment of laborers, as well as by environmentalists who said the tower would act as a power vacuum, increasing the city's already massive carbon footprint.

But despite the criticism, many say the edifice, believed to have cost $1.5 billion to build, is an architectural marvel.

The tower's height has been kept a closely guarded secret until now. Developer Emaar Properties PJSC will reveal the height -- known to exceed 800 meters (2,625 feet) -- on Tuesday and Dubai's ruler will inaugurate the opening.

Experts believe Dubai's recent financial troubles have not hurt sales of approximately 1,100 residential units in the Burj -- meaning tower in Arabic -- saying they were nearly all sold.

Dubai's real estate sector crashed at the end of 2008 when the global financial crisis hit the emirate after a six-year economic boom. Thousands of jobs were slashed and projects worth billions of dollars were canceled or delayed.

With analysts suggesting tax-free Dubai might sell some of its assets to boost revenues and slash $80 billion in debt, many wondered if the tower was on the list for grabs.

Dubai, with few natural resources of its own, expects a budget deficit of 2 percent of GDP this year.

In December, the emirate received a $10 billion lifeline from neighboring Abu Dhabi to repay a $4.1 billion bond for Nakheel, a property arm of indebted Dubai World, and other obligations.

(Editing by Elizabeth Fullerton)