The public spaces and rooms at the 906-bedroom hotel completed a refurbishment ahead of the mayor of London Sadiq Khan signing off plans to redevelop the site.
A spokesperson for the hotel, which is the largest Holiday Inn in Europe, said the redevelopment is "some way off" and at this stage it is "very much business as usual" at the hotel.
Patrick O'Connell, head of hotels for Queensgate Investments, which bought the hotel in 2015, said: "While we have long-term plans to redevelop the hotel, this current refurbishment demonstrates our commitment to continuing to deliver a world-class hotel with exceptional conference facilities in the immediate future."
The hotel now has the Holiday Inn open lobby concept as well as a new lobby restaurant, Ashburn SW7.
Queensgate and developer Rockwell applied to replace the existing hotel with a larger property encompassing a 749-bedroom hotel, 340 serviced apartments, a conference centre, restaurants, bars, health spa and conference facilities. The development was also set to include 46 homes, 20 of which were to be available at social rent levels for Londoners on low incomes.
The proposals were rejected by the Royal Borough of Kensington and Chelsea in September 2018, before the mayor intervened to subject the plans to further scrutiny. Following an agreement to increase the number of homes to 62 and make all of them affordable, the mayor signed off the plans.