Sporting issued a statement on their website confirming Everton's bid and, although Moutinho says he wants to leave, also made it clear they are determined to keep the player.
"(Sporting) reveals that the personal reasons that the player pleads to be transferred are completely unrelated to Sporting and the working relationship it maintains with the player," read the statement.
"... and, as such, it cannot justify in any way an act of management that does not adequately defend the interests of the company and its shareholders."
Everton are yet to make a major signing this summer but have been linked with selling striker Andy Johnson.
Johnson's exit could give them the ability to raise the funds to up their offer for Moutinho, who is seen as one of his country's emerging talents, and test Sporting's resolve.
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