The Burj Dubai Tower is now the world's tallest free-standing structure, reaching a soaring 555.3 meters into the sky. Work on the building is still underway, and officials say it will climb 800 meters when it is completed.

"The Burj Dubai tower has now reached 555.3 meters, and also scaled 150 livable levels, the largest number of storeys for any building in the world," developer Emaar Properties said.

"This architectural and construction masterpiece is truly an inspirational human achievement that celebrates the can-do mindset of Dubai," Emaar Chairman Mohamed Alabbar said.

"Burj Dubai is setting new world records in construction of super-tall buildings, and the accomplishment of being the world's tallest free-standing structure is another defining moment for the multinational team of over 5,000 people who are using their collective intelligence to make this iconic structure a symbol of human achievement," he added.

The battle for world's tallest isn't over yet, as the neighboring Al-Burj Tower is set to hit a reported 1,200 meters when it is completed in 2009.