Napoli want an attacking asset in case Khvicha Kvaratskhelia leaves this month.
TMW say Napoli are interested in former Bologna striker Zirkzee, although they have been warned United are only interested in an outright sale.
They are also determined not to sell at a loss, having spent €40 million plus agent commissions on the Dutchman.
Juventus are also in contact, but like Napoli would prefer a loan-to-buy arrangement.
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