ITALY (REUTERS) - Italian Serie A side AC Milan have signed striker Andre Silva from Porto for a fee that could rise to €40 million ($61 million), the Portuguese club said on Monday.

The 21-year-old, who has signed a contract that will keep him at Milan until June 2022, made 32 league appearances for Porto last season, scoring 16 goals.

He also scored four times in eight appearances in last season's Champions League.

Milan paid Porto an initial €38 million for Silva, with a variable component that could see the fee rise by an additional €2 million, the Portuguese club said in an official club statement.

Milan finished sixth in Serie A last season, earning a place in next season's Europa League qualifiers and ending a three-season absence from European competition.