Mesic described the Holy Father as "a champion of a better and more just world" who had spread the message of peace, tolerance and solidarity.
"The Croatian people will remember John Paul II as a true friend, an advocate of our right to freedom and independence, whose messages of reconciliation and tolerance we will try to build into the future of this country and this region," Mesic wrote.
Mesic told reporters he had met the Pope several times and that all his meetings with him had been held in a friendly atmosphere.