Cristian Romero is undergoing a medical at Tottenham after Spurs agreed a £47m deal with Atalanta for the defender.
Spurs increased their offer to £42.7m (€50m) plus bonuses, making a total package worth £47m (€55m) for the Argentina centre-back.
Romero, 23, will undergo the second part of his Tottenham medical in Italy on Thursday before flying to London to complete his move.
The proposed transfer will make him the second most expensive signing in Tottenham's history after Tanguy Ndombele, who joined for £54m in July 2019.
Romero made 42 appearances in all competitions last season as Atalanta finished third in Serie A and were runners-up in the Coppa Italia.
Atalanta have secured Juventus centre-back Merih Demiral as Romero's replacement.
Tottenham have already signed goalkeeper Pierluigi Gollini on an initial season-long loan deal from Atalanta, with the option to make it a permanent deal.
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