The 25-year-old has recently been strongly linked with the likes of Tottenham and Manchester United.
United have reportedly already had a £20million bid for Moutinho rejected.
“Clubs cannot just not sell. We really want him to stay but this is football and there are such things as release clauses,” Porto boss Vitor Pereira told Abola.
“The only thing we can do is achieve results with what we have got.”
Moutinho’s current contract with Porto expires in 2015.
