The Holy Father is arriving during a serious cultural, economic and political crisis which is actually a deep crisis of the spirit spreading despondency, deepening divisions and dissatisfaction, the letter said, adding that the pope was coming at a time when Croatia was about to join the European Union, "which faces us with new questions and challenges full of expectation and uncertainty."

The main motive for the visit is the national meeting of Croatian Catholic families, which Croatia will celebrate for the first time, and a prayer at the grave of the beatified Alojzije Stepinac, the letter said.

"Marriage is the source and the foundation and the family is the first and a lifelong station of human society. The family is also the first school of social virtues without which human society cannot survive, because all the virtues it appreciates and needs are born and inspired mainly in the family. Family upbringing is crucial for the life of the entire society," the bishops said.

The Church understands well the difficulties the modern Croatian family is undergoing, the letter said. Many young people in Croatia postpone marriage because of unemployment and the fact that they cannot afford a home, divorces are on the rise, addictions and domestic violence too, and living together for a trial period, without commitments, which openly attacks the value of marriage and family, is becoming widespread, it added.

The bishops said the national family meeting was aimed at promoting marital and family values and showing Croatian Catholic families that they were not on their own.

On June 4, the pope is scheduled to meet representatives of culture, science, art, the economy, politics, sports, religious communities and diplomats as well as young people. On June 5, he is to celebrate Eucharist at Zagreb's hippodrome and later in the day celebrate Mass in the Zagreb Cathedral.