The iconic Marina Bay skyline is set to change, with the addition of a stand-alone tower to be built next to the three capped by a sky park.
Marina Bay Sands' (MBS) new luxury hotel will house 1,000 suites and have its own sky roof with a swimming pool and restaurant.
Downstairs, visitors will pass through a "dramatic atrium" on the way to its eateries, ballrooms and exhibition halls, operator Las Vegas Sands said in a statement yesterday.
Its design team will include acclaimed architect Moshe Safdie, who was behind the original MBS' unique structure.
An arena that can seat 15,000 will also be built and optimised for concerts, with the aim of drawing A-list artists.
Its planned state-of-the-art production capability will appeal to performers "who might not have previously included South-east Asia on their tours", said Las Vegas Sands, which is sinking $4.5 billion into the expansion of its integrated resort (IR) in Singapore's downtown district.
More space will also be dedicated to business events, it added.
Work on the new project will begin "quickly", though no timeline for its completion has been made available yet.
Las Vegas Sands chairman and chief executive Sheldon Adelson said that MBS has "exceeded all of our hopes in growing leisure and business tourism in Singapore". It hosted 3,680 events at its Sands Expo and Convention Centre last year alone.
MBS' president Rob Goldstein added that the additional hotel rooms are important to meet demand from leisure and business tourists as well as premium gaming customers.
Mr Wong Soon-Hwa, chairman of the Pacific Asia Travel Association's Singapore Chapter, said that nearly a decade since they opened, Singapore's two IRs are due for a major change, particularly given the increasing competition in the region.
He noted that while the Government is concerned about the social impact of gambling, "after 10 years of working with the two parties, there is a certain degree of trust that has been built".
"So in a way (their expansion) is preferable to having a third IR, especially when the market is only this big," he said.