The New York edifice, whose official name is One World Trade Centre, takes the title as tallest after including the spire installed this year, which raises it from 417 meters to 542 metres, leaving the 442 metres of the Chicago skyscraper behind.

Once complete, the Freedom Tower will be the third tallest building in the world, trailing only the Burj Khalifa in Dubai and the Makkah Royal Clock Tower in Mecca, Saudi Arabia, the CTBUH said.