DUBAI // Burj Khalifa's observation deck has been closed to the public until further notice, little more than one month after it opened, due to problems with the power supply. A spokesman for the world's tallest tower issued a statement explaining the sudden closure this afternoon was to conduct building maintenance and an upgrade, work that was deemed necessary due to the high level of visitors over the last month. "Technical issues with the power supply are being worked on by the main and subcontractors and the public will be informed upon completion," the spokesperson said. Guests who booked advance trips to the 124th floor observation deck will be given refunds or allowed to book a date when the deck reopens, although no indication was given as to when that would be. The mixed use tower's apartments are to be handed over its owners next month while the Armani hotel is to open March 18. Burj Khalifa, the 828-metre building from the developer Emaar, opened on January 4 with a large fireworks display. Although an official count has not been provided, thousands of tourists and local residents have flocked to the tower since it opened. eharnan@thenational.ae