Millennium & Copthorne's (M&C) boss Tony Potter has quit his role after seven years with the company.
He said he had decided to leave the company to relocate outside the UK for family reasons.
Potter has been a main board director at the company for seven years. He was chief operating officer for five of those years, and has been chief executive officer for the past two years.
"Whilst I am sorry to be leaving, I believe that now is the right time for me to take on new opportunities," said Potter.
M&C chairman Kwek Leng Beng said he was disappointed to see his chief executive go, but fully understood his reasons for doing so.
Potter will continue in his role while a replacement is sought.
• An Independent report, Pay for Performance, published in May showed Tony Potter's total remuneration had grown 15% to £713,000 in the past five years.
By Chris Druce