Ekstra Bladet says Villa have made an opening bid of €2 million for the Denmark international - which has been immediately turned down.
Ajax have informed Villa to up their offer to €2.7 million if they want to close a deal.
Kenny Boilesen, the player's father, says they're staying calm about the situation.
"If the right club does not come, Nicolai will just continue with Ajax and will become a free transfer next year."
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