Mesic and senior officials from 63 three countries are taking parts in the Francophone Summit that is being held in Romania's capital on Thursday and Friday.
Croatia wants to meet its strategic objectives and join Euro-Atlantic associations, but it must not be oriented only towards European countries.
"We are here to introduce Croatia to the market of Francophone countries, to reaffirm the French language in Croatia and to have 63 Francophone countries support Croatia's candidacy for a nonpermanent membership of the UN Security Council, the Croatian president said.
Croatia joined the International Francophone Organisation in 2004 as an observer and this year it is its first time for the Croatian leader to attend a Francophone summit.
On the margins of the meeting, Mesic held bilateral talks with the presidents of Latvia, Albania and Bulgaria and briefly met French President Jacques Chirac.