"As long as we are transferring our citizens to the Hague-based tribunal, it will not be possible to make the public in Croatia accept a decision not to extradite foreign nationals to that court," Mesic told the press after attending the 40th anniversary of Zagreb's Health Polytechnic on Friday.
Mesic reiterated his position on the non-extradition of US citizens to the ICC, stating that he was against Croatia signing such an agreement with the United States.
Some media have reported that Croatia and the USA could sign an agreement on the non-extradition of US citizens to the ICC during a visit by US Vice President Dick Cheney scheduled for 5-7 May.
The Hague-based ICC is the first international body in charge of war crimes trials, which was established on the basis of the Rome Statute and which started operating in mid-2003.
The USA has so far signed bilateral agreements on the non-extradition of its citizens with at least 100 countries on the basis of Article 98 of the Rome Statute, which provides for the possibility of a country signing a bilateral agreement with another country that is not a party to the ICC in order to exempt its citizens from the ICC's jurisdiction.
The EU provides strong financial and political support to the ICC and believes that the signing of such an agreement with the USA is incompatible with membership of the EU.
Following instructions from the EU, Croatia refused to sign such an agreement with the USA in June 2003, which resulted in its losing US military assistance.
Although in the meantime the USA has attempted several times to have the decision changed, Croatia has stuck to its decision, refusing to sign the agreement on Article 98 of the Rome Statute.