Benfica are referring interested clubs to Goncalo Ramos' buyout clause.
The Sun says Ramos is wanted by Manchester United for £25million, while Newcastle were targeting the Benfica forward - who played against the Magpies in pre-season - last summer.
However, his release clause is understood to be €100million.
Ramos, who has represented Portugal at every level since under-17 but is yet to earn a senior cap, has already bagged eight goals in 12 games this season.
At 21, the forward would be a long-term option for any Premier League side. The Red Devils only have 37-year-old Cristiano Ronaldo as a striker option but have played Marcus Rashford there in 2022-23.