Mariah Carey was reportedly paid almost $1 million ($1.83 million) to perform for the Sultan of Brunei's son.
The diva played the show at the Dorchester Hotel on New Year's Eve after being invited by 31-year-old billionaire Prince Azim.
While a representative for Mariah confirmed she performed at the event, they wouldn't reveal how much she was paid.
"It was a private party so we don't discuss the fee," the representative told The Daily Mail.
"Mariah has known Prince Azim for many years. They are friends and have done a lot of charity work together."
Also performing at the event for the sultan's son was Diana Ross, with one guest taking to Twitter to share their thoughts on the evening's entertainment.
"What a night! Mariah Carey and Diana Ross singing us in to 2014," the user wrote.
"Thank you Prince Azim for such an incredible night!"
It is said Mariah played around three of her hit singles, and lead a chorus of Auld Lang Syne.
The hit-maker recently attracted criticism from human rights campaigners for performing in front of Angolan dictator José Eduardo dos Santos for a similarly large sum, after apologising for singing for Libyan despot Muammar Gaddafi in 2008.