The plane, which Amnesty International (AI) claims was used by the CIA to transport terror suspects and which reportedly also used Dubrovnik airport, does not require diplomatic permission from the Foreign Ministry, unnamed sources at the ministry said.
Last Wednesday AI released a report on its web site saying that the Boeing 737 plane which international humanitarian organisations claim was used by the CIA from 2002 to 2005 for the transport of terror suspects, twice used Dubrovnik airport in 2004.
Foreign embassies in Croatia have to seek permission from the Foreign Ministry for the landing or overflight of planes from their respective countries. The Foreign Ministry forwards such requests for approval to the ministries of defence and transport and if they are approved, the Foreign Ministry grants permission for a landing or overflight, the same sources said.
State planes are civilian planes carrying state officials or VIPs and military, police and customs planes. The plane in question was not cited as a state plane, which means that it was a civilian plane, the sources said.
A possible decision to seek an explanation about the plane from the United States should be made by the government, the sources said.
Last week Croatia sent its answer to Council of Europe Secretary-General Terry Davis who had requested the clarification of the procedure for the supervision of foreign secret services and the use of Croatia's air space and airports.
Last year Davis requested the Council of Europe member-states to report how they supervised the operation of foreign secret services on their territory and who was using their air space and airports and for what purpose. By February he received answers and then asked for additional explanations from most member-states.
Croatia is one of the 46 countries requested to clarify the procedure and one of the 37 countries which have to submit additional explanations, the sources at the Foreign Ministry said.
One of the requested explanations refers to whether there has been an official in Croatia actively or passively involved in the illegal transfer of arrested persons from one country to another.
In its reply to Davis Croatia explained that the parliament is in charge of supervising secret services, through the office of ombudsman, as well as that cooperation between foreign and Croatian secret services is being supervised. With regard to the question about officials actively or passively involved in the illegal transfer of arrested persons, the Foreign Ministry answered that according to information collected from a number of sources, there had been no such cases in Croatia.