Manchester United would have to pay €75m to sign Porto defender Eder Militao, according to Portuguese outlet O Jogo.
The 20-year-old has been linked with Manchester United, Liverpool and Real Madrid, however, any deal for the youngster has been complicated by a clause in his contract.
United are working on a number of centre-back targets, with Napoli defender Kalidou Koulibaly at the top of the list.
Militao was previously viewed as a cheaper alternative before his release clause was reported.