Striker Dominic Adiyiah could miss Ghana's pre-World Cup training camping after being named in AC Milan's 18-man squad for an international friendly against D.C. United on 26 May.
Ghana will hold its camping from 24-27 May in France before playing Holland in a test match on 1 June in Rotterdam.
If not released, the 2009 World Youth Golden Shoe and Ball recipient will miss Milovan Rajevac's assessment period and can join his international team mates in Holland.
Adiyiah is likely to make Ghana's final 23-man World Cup squad.
He signed for the seven-time European champions in January and regarded as an asset despite an inactive half-season spell at the San Siro.
Among the players confirmed are Brazilians stars Ronaldinho and Alexandre Pato, and Dutch midfielder Clarence Seedorf.
Additionally goalkeepers Dida and Christian Abbiati; defenders Luca Antonini, Marek Jankulovski, Massimo Oddo, Giuseppe Favalli, Alessandro Nesta and Marcus Diniz;
Midfielders Ignazio Abate, Davide Di Gennaro, Mathieu Flamini and Massimo Ambrosini; and forwards Mancini, Filippo Inzaghi