"The united Europe and NATO are not rivals, but partners, which is why cooperation between the two organisations cannot be dictated from only one direction," Mesic said at the 50th General Assembly of the Atlantic Council in Rome.
Mesic underlined that the United Nations should not be excluded from the cooperation between the EU and NATO in international relations. "We in Croatia support such multilateral politics, which does not promote only unilateral interests, but also cooperation and standards."
Mesic said that Croatia, learning from its experience of war, was aware that it could not develop only on the basis of its own safety and stability but also on the basis of a safe and stable neighbourhood.
He said that Croatia and other countries aspiring to join the EU and NATO should fulfil their obligations "without delay and without excuse" rather than just insist on common values.
Mesic, together with Presidents Alfred Moisiu of Albania and Branko Crvenkovski of Macedonia, met NATO Secretary General Jaap de Hoop Scheffer behind closed doors.
Earlier in the day, the Croatian president held a separate meeting with his Italian counterpart, Carlo Azegli Ciampi.