Australian lawyer Melinda Taylor and three of her colleagues are being held in detention in Libya. They were in the town of Zintan to visit with Saif al-Islam, who is detained there and wanted by the ICC on charges of crimes against humanity allegedly committed during last year's war.
Libyan authorities are holding the ICC lawyers under house arrest. Taylor is accused of passing documents to Saif al-Islam, late Libyan leader Moammar Gadhafi's son, from an ally.
Geoff Roberts, an ICC lawyer and Taylor's husband, told The New York Times the Libyan charges were baseless.
"She is very aware of her ethical responsibility as a lawyer, both to her court and to her client (Saif al-Islam)," he said.
The Kremlin this week called on the U.N. Security Council to weigh in on the issue. A Russian lawyer is among the four detained.
The ICC reminded Libyan authorities that its lawyers are protected by immunity.