According to Property Week Cola Holdings, which acquired The Westbury in 1999, is looking to offload the hotel as part of a wider £1bn portfolio sale.
It is expected to be put on the market once the sale of the nearby Ritz hotel is completed.
Last October it was reported that the billionaire Barclay brothers, who have owned The Ritz since 1995, were considering an £800m sale of the iconic property.
The Westbury opened in 1995 and is home to the Michelin-starred AW restaurant, which made headlines last year following the dismissal of long-time chef patron Alyn Williams.
Cola Holdings was founded by Kurdish born Bakir Cola. Its portfolio includes the Hilton London Kensington Hotel, which it bought for £260m in 2018.