Milan have reportedly made an offer to Manchester United to take Diogo Dalot on loan with option to buy, but the Premier League side want an obligation.
The 22-year-old full-back spent this season at San Siro on a dry loan, making 33 competitive appearances, with two goals and three assists.
According to Calciomercato.com, a proposal has been made to Manchester United to extend the loan and add an option to buy at the end of the 2021-22 campaign.
That was turned down, because the Premier League side will only let Dalot go on another loan if there is an obligation to buy.
The cost of the operation would be circa €16m plus €2m in performance-related bonuses for the Portugal Under-21 international.