According to reports, Liverpool has offered €30 million for Leoni, and Parma is willing to accept the deal.
Last season, Leoni had a successful campaign in Serie A, helping Parma avoid relegation under the guidance of coach Cristian Chivu.
Leoni had been linked to Inter Milan earlier this summer, but it seems he is now on the verge of joining Liverpool.
Signing Leoni will not mean the end of Liverpool's pursuit of Crystal Palace defender Marc Guehi.