Four International Criminal Court staff detained in Libya since early June are expected to be released on Monday, according to the court.
The four were detained in the western mountain city of Zintan after local officials levelled accusations of spying at one of them, Australian lawyer Melinda Taylor, who was sent by the ICC to represent the son of slain dictator Muammar Gaddafi.
The ICC also said the court's president, Sang-Hyun Song, would go to Libya on Monday, Reuters reports.
In June, the ICC expressed regret to Libyan authorities in what seemed to come close to an apology designed to secure the release of its employees.
ICC spokesperson Fadi El Abdallah said the release of the four staff is expected to happen on Monday.
Ms Taylor was appointed by the court to represent Saif al-Islam Gaddafi, whom the ICC wants extradited to face charges of war crimes allegedly committed during the uprising that toppled his father last year.
Three other ICC officials, from Lebanon, Russia and Spain, were also detained.
Libya has said it wants to try Saif al-Islam in its own courts.
Earlier on Sunday, an official from the Libyan prosecutor general's office told Reuters an ICC delegation would arrive to "offer an apology for the acts their team committed."
Officials in Zintan, which is only loosely under the Tripoli's authority, accused Ms Taylor of attempting to carry concealed recording devices and sensitive documents to Saif al-Islam, who has been in prison in a secret location since his capture last November.