And the 27-year-old, who has two years remaining on his current deal at Porto, admits that his future is currently up in the air.
"I do not know what will happen," he told radio station La FM. "I have a contract for two more years with Porto and I know there is interest from several clubs.
"It's normal if a player is playing well, but I have always respected my contracts.
"Only time will tell what will happen."
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