DUBAI (Reuters)- Started at the height of the economic boom and built by some 12,000laborers, the world's tallest building will open on Monday in Dubai asthe glitzy emirate seeks to rekindle optimism after its financialcrisis.

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

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

With investor confidence in Dubai badly bruised by the emirate'sannouncement in November that it would seek a debt standstill for oneof its largest conglomerates, the Burj Dubai is seen as a positivestart to the year after a bleak 2009.

The project has been scrutinized by human rights groups, who haveobjected to its treatment of laborers, as well as by environmentalistswho said the tower would act as a power vacuum, increasing the city'salready 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 toexceed 800 meters (2,625 feet) -- on Tuesday and Dubai's ruler willinaugurate the opening.

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

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

With analysts suggesting tax-free Dubai might sell some of its assetsto boost revenues and slash $80 billion in debt, many wondered if thetower 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 fromneighboring Abu Dhabi to repay a $4.1 billion bond for Nakheel, aproperty arm of indebted Dubai World, and other obligations.