U.S. investment firm RedBird Capital Partners has agreed a 1.2 billion euro ($1.3 billion) deal to buy Italian football champions AC Milan, the club said on Wednesday, while current owners Elliott will retain a minority investment.

The transition to new ownership will take place over the summer, with an expected closing of the deal no later than September, the club statement added.

Milan have just won the Italian Serie A league title for the first time in 11 years.

UEFA starting to gather evidence for Champions League probe  

"We are honoured to be a part of AC Milan's illustrious history and are excited to play a role in the club's next chapter as it returns to its rightful place at the very top of Italian, European and world football," RedBird founder and managing partner Gerry Cardinale said in a statement.

RedBird is already an investor in Fenway Sports Group, the owner of Liverpool FC and the Boston Red Sox baseball team. RedBird also has a controlling stake in French football club Toulouse.

"RedBird's investment philosophy and track record in team ownership has shown that football clubs can be successful on the pitch and sustainable off it," Cardinale added.