The forward has been the subject of intense speculation in recent months following some stellar performances for the Italian giants.
The 23-year-old has already bagged 13 goals and 13 assists in all competitions this term, leading to substantial interest from Chelsea and Real Madrid in his services.
The Blues are looking for a new number nine as they look to challenge at the top end of the Premier League next season under their new boss, with Mauricio Pochettino looking like the man set to take his place in the dugout.
As for Madrid, the Spanish giants are looking at long-term solutions to replace Karim Benzema, with the 35-year-old moving into the final years of his career.
But both clubs have been dealt a blow with Leao committing his future to Rossoneri.
The Portuguese forward joined AC Milan in the summer of 2018 having shone for French club Lille where he helped them to the semi-finals of the Champions League.
Since then, Leao has made 159 appearances for Milan, scoring 40 goals in the process and establishing himself as one of the best young forwards on the continent.
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He also played a key role in helping Milan to the Scudetto in 2021, as well as winning 18 caps for Portugal and scoring three goals - two of which came at the World Cup in Qatar.