But it looks like Saudi Arabia could make good on its blueprints.
Two major state development arms, the Jeddah Economic Co and Alinma Investment, have announced a US$1.2 billion ($1.8 billion) financing deal to fund the 200-storey tower and surrounding developments.
Plans call for the building to be completed in 2020.
Already, 26 stories are built. An observation terrace is planned for floor 157 of the tower, shaped like a gleaming shard. But even more startling than the size is the timing. Saudi Arabia is in a relative slump by oil giant standards.
Low crude prices have sharply cut the revenue flow from the years of triple-digit levels per barrel. Add to that the costly Saudi-led war in Yemen against anti-Saudi rebels that Riyadh claims are backed by arch-rival Iran.
So why now?
"With this deal, we will reach new, as yet unheard of highs in real estate development," boasted Mounib Hammoud, the CEO of the Jeddah Economic Co - clearly with pun intended as a message to Saudis and others questioning whether the country will remain the economic powerhouse of the region, or get caught in a long and draining war in Yemen.
The project also is something of a statement piece for the Saudi King Salman, who will mark his first year in charge in January. Many of Saudi Arabia's landmarks - including hard-charging development in the Islamic holy city of Mecca - are legacies of Salman's predecessor, the late King Abdullah.
No doubt that the nearly 80-year-old Salman hopes to be around for a possible ribbon-cutting at the Jeddah Tower. If it happens, the tallest-skyscraper bragging rights would shift to its fifth country in a little more than a generation.
The Burj Khalifa officially took the title in 2010 from Taiwan's 509m Taipei 101 tower, which held the top spot since 2003. Before that it was the 452m Petronas Towers in Kuala Lumpur, Malaysia, which nudged out Chicago's 442m Sears Tower in 1998.
Since 2010, some other lofty buildings have joined the ranks of the 10 top - including the Clock Tower in Mecca and China's Shanghai Tower - but did not crest the Burj Khalifa.
- Bloomberg