Matthijs de Ligt has agreed a contract at Juventus and Ajax must now negotiate with the Serie A champions, according to the defender's agent, Mino Raiola.
Netherlands international De Ligt has been at the centre of intense transfer speculation, his performances for club and country over the past year seeing him linked to clubs including Juve, Paris Saint-Germain, Barcelona and Manchester United.
It has been reported over the past week that the 19-year-old has accepted a five-year deal offered by Juve, worth in the region of €9million.
Raiola told Dutch newspaper De Telegraaf that De Ligt has agreed to the contract and urged Ajax to make a decision over the player's future.
Juve are said to have opened with a bid of €50m, which was rejected.
"Agreements have been made with Matthijs and it is up to Ajax how to deal with this," Raiola told De Telegraaf.
Raiola also stressed it was "out of the question" that De Ligt would attempt to force a move to Turin by refusing to return for the start of Ajax's pre-season training.
He is due to report for the Eredivisie champions on Monday, although rumours in Italy suggest Juve hope to fly him out for a medical as early as Wednesday.