The boss of Millennium & Copthorne (M&C) Hotels has stood down three months after taking over.
Group chief executive Jennifer Fox and M&C "have mutually agreed" she will leave with immediate effect, the company said.
It is thought there were differences of direction between the industry veteran and M&C's chairman and majority owner.
Ms Fox, who is being replaced on an interim basis by chief of staff Tan Kian Seng, will receive a £1m pay-off.
Ms Fox has spent 30 years in the hospitality industry, including as president of Fairmont Hotels & Resorts and 10 years with InterContinental Hotels.
She started work at M&C on 19 June, replacing Aloysius Lee, who had resigned in January.
M&C did not give reasons for her departure in a short statement to the London Stock Exchange.
A separate statement on M&C's website said Ms Fox would receive her contractual entitlement of a £1m pay-off.
At the time of her appointment, Ms Fox spoke of her ambitions for the company, whose brands include Millennium, Grand Millennium, Copthorne and Kingsgate.
"I see this as a significant opportunity at a time of great change in our industry," she said.
But Ms Fox joined at a time when M&C's revenues were under pressure from rising costs, especially at its hotels in London.
She was working on a new strategic plan for the group, and had made two key appointments; new heads of global marketing and human resources.
But it is thought that there were differences with billionaire chairman and majority owner Kwek Leng Beng.
Last year, he wanted to take M&C private, warning that terrorism scares, industry overcapacity and political uncertainty in Europe were affecting the business.
Last month, the hotel group reported that revenues in the first half of the year fell to £477m, compared to £485m the previous year. The chairman described the results as "mixed".