Manchester United have confirmed that Richard Arnold has stepped down as CEO of the club, with Patrick Stewart set to move into the role on an interim basis.

Arnold's position had been called into doubt since it was revealed that British billionaire Sir Jim Ratcliffe was preparing to buy 25% of the club.

The owner and founder of INEOS is expected to make major changes at management level, with the jobs of football director John Murtough and director of football operations David Harrison also called into doubt.

A report earlier on Thursday said that Arnold, who has been with Man United since 2007, would leave his role as CEO, and it has now been confirmed by the 20-time English champions.

"Richard Arnold has decided to step down as Chief Executive of Manchester United after 16 years with the club," read a statement on the English club's official website.

"Patrick Stewart will take over as interim CEO, in addition to his existing role as General Counsel, with Richard continuing to provide transitional support until the end of December. A search process will be carried out for a new permanent CEO."

According to The Athletic, ex-Juventus chief executive Jean-Claude Blanc, who is currently working with INEOS Sport, is one of the main candidates to step into the position on a permanent basis.

Man United executive co-chairman Joel Glazer told the club's official website: "I would like to thank Richard for his outstanding service to Manchester United over the past 16 years, and wish him all the best for his future endeavours.

"We are fortunate to be able to call on the deep knowledge and experience of Patrick Stewart to provide interim stability and continuity as we embark on a search for a new permanent CEO."

Meanwhile, Arnold said: "It has been an incredible privilege to serve this great football club for the past 16 years. 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."

Stewart also commented on his new position, revealing that he will "support the search for a new permanent 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," he said.

Ratcliffe is expected to take over the football department upon his arrival, with a deal, which will allegedly cost around £1.3m, set to be completed before the end of the international break.

On the field, Man United have struggled this season, but the team have won four of their last five in the league, including back-to-back 1-0 successes over Fulham and Luton Town.