Belgian international Dries Mertens has admitted that his future with Napoli is currently unclear.

The 29-year-old has scored 28 goals in all competitions for his Italian club this season, including 22 times in Serie A.

It was reported in March that Manchester United had held 'secret talks' with Mertens, with Red Devils boss Jose Mourinho believed to be interested in signing the attacker at the end of the season.

Mertens's current deal in Naples will expire next summer, and the 57-time Belgium international has refused to offer any guarantees over his future at Napoli.

"We are focused on Champions League qualification at the moment and we know it all depends on us but we also know that anything can happen. Opponents are tired and they can make some mistakes," Mertens told ElfVoetbal.

"I'm optimistic. As for my future I can't say anything at the moment, we'll see what's going to happen."

Mertens scored five times in eight Champions League appearances for Napoli this season during the Italian side's run to the round of 16.