Portsmouth are taking Inter Milan to court over money they claim is owed them from the transfer of Sulley Muntari, BBC Radio Solent reports.
The Championship side's outgoing administrator Andrew Andronikou says payments owed from Muntari's sale in 2008 are "heavily overdue".
The clubs will go to court in Italy later this month over £900,000 which Pompey say they are owed.
Muntari's first club Udinese are also involved in the case.