Sporting Lisbon president Frederico Varandas says Manchester United will have to offer more than 56m for Bruno Fernandes.
Reports in Portugal last week claimed United were prepared to offer 50m for the 24-year-old.
But Varandas insists Sporting won't accept any less than their valuation.
"I don't know if there are many or if there are few [interested clubs]," Varandas told RTP at Lisbon Airport.
"What I know, a lot has been spoken of values, coming to the press, 55m, 62m for that he doesn't leave, for sure.
"If Bruno Fernandes leaves, players with quality will come. But if Bruno leaves."
