RIYADH—Saudi Arabia's Prince Alwaleed bin Talal announced plans to build the world's tallest building in Jeddah less than two years after the Burj Khalifa opened in Dubai at a height that many thought wouldn't be surpassed for years.

The planned tower will soar to 3,281 feet (1,000 meters) and will include a hotel, luxury condominiums and offices. It would dwarf the Burj Khalifa, which is 2,717 feet (828 meters), and would also be the world's tallest man-made structure.

Prince...