Richard Arnold will leave his role as Manchester United CEO ahead of Sir Jim Ratcliffe's imminent arrival as a minority shareholder.
United released a statement confirming the news on Wednesday afternoon.
"It has been an incredible privilege to serve this great football club for the past 16 years," Arnold said.
"Through highs and lows, the constant has been the dedication of our employees and fans. I would like to thank all of them for their loyalty and commitment, and wish everyone associated with the club the very best for the future."
Current chief legal counsel Patrick Stewart will replace Arnold as interim CEO.
"Together with my leadership team colleagues, my job will be to ensure that the club's foundations remain stable while we embrace changes that can make us stronger over the long term, on and off the pitch, and to support the search for a new permanent CEO," Stewart said.
Ratcliffe's £1.3 billion investment for a 25% stake in the club is close to being finalised.
Sources have told ESPN that football director John Murtough's position is also under threat with Ratcliffe keen to bring in INEOS director of sport Sir Dave Brailsford.
Murtough was appointed in March 2021 and was heavily involved in the decision to bring in Erik ten Hag as manager in 2022. Paul Mitchell is one of the names in the frame to replace him.
Arnold took over the role of United's most senior executive from Ed Woodward in February 2022.
His departure from the club will have to be announced to the New York Stock Exchange.
Ratcliffe is set to become a minority shareholder nearly a year after owners the Glazer family announced they would consider "strategic alternatives" including a full sale of accepting minority investment.
Ratcliffe is set to have influence over the football side of the business once his investment is confirmed.