An agreement has been reached for Kyril Louis-Dreyfus to buy Stewart Donald's controlling interest in Sunderland, paving the way for a takeover.
The Frenchman will become chairman in the new year, subject to approval by the English Football League.
Donald, who stepped down as chairman in July, holds a 74% stake in the club.
"It's been no secret that I have been looking for some time to find the right person to take Sunderland forward," Donald told the club website.
"During the course of the last year there have been a lot of different people wanting to take over.
"However, even though it is a matter of public record that some of those bidders offered me more money, I felt that they offered less to the club and to the community.
"Whereas from the early meetings with Kyril, his family and advisers, I have been greatly impressed with their knowledge and understanding, learned over a long period as owners of major football clubs in Belgium and France.
"I believe that experience, combined with a good plan, will provide a platform for the club to progress and I look forward to watching that progress from afar."
Former Eastleigh owner Donald has been Sunderland's majority shareholder since May 2018, when he took over from previous owner Ellis Short.
He has been trying to sell the Black Cats for the past 12 months and said he was "desperate to get out" of the League One club in the summer.
Aged just 22, Louis-Dreyfus, the son of former Marseille owner Robert Louis-Dreyfus, would become the youngest chairman in English football.
"We respectfully await the EFL's approval for this transaction," Louis-Dreyfus said.
"Nonetheless it would be remiss of me at this stage not to emphasise what an enormous honour it would be for me to become involved with such a historic club, in a city renowned for its rich football culture going back to 1879.
"Many will be aware of my family connections to the industry and, in acquiring Sunderland AFC, I understand the responsibility that's placed upon me as the custodian of the club's future.
"If we all play our parts, I firmly believe we can restore Sunderland AFC to the top tier of English football and I can't wait to get started."