Mesic stressed it was also important to agree on principles for future joint actions in the region.
The Croatian president said the security concept did not include only military but other dimensions as well, such as the economy, the protection of minority rights and freedoms, the protection of democracy and the rule of law.
"The threat of armed conflict is being reduced but threats such as organised crime, illegal migrations, drugs, global terrorism and proliferation of mass destruction arms are increasing," Mesic said, adding that the main reasons for that were corruption, poverty and weakness of state institutions.
He said Croatia addressed organised crime as a serious problem, expressing conviction that joint cooperation in fighting organised crime and international terrorism was possible. Mesic said Croatia would fully contribute to those efforts.
The meeting in Karadjordjevo, hosted by Serbian President Boris Tadic, was also attended by Albanian President Alfred Mojsiju, member of Bosnian Presidency Borislav Paravac, Montenegrin President Filip Vujanovic, Macedonian President Branko Crvenkovski, Romanian President Trajan Basesku and the European Commission Vice President Franco Frattini
The event was covered by 130 reporters from countries of the region.
Before the conference, Mesic held talks with Serbian President Tadic on the situation in the region and the two countries' mutual protection of minorities.