Croatian President Zoran Milanovic had a private one-on-one meeting with Pope Francis in Vatican City on Monday, at the start of his official visit to the Vatican.

Gift exchange is customary at the end of private audiences and according to unofficial sources, Milanovic will present the Pope with a 14th-century Glagolitic Missal of Duke Novak.

The letters of the missal were later used for the first Croatian printed book, Missale Romanum Glagolitice.

The missal was written by the royal knight Novak Disislavic as a pledged gift to a church, where he was to be buried after death.

During his official visit to the Vatican, Milanovic is also scheduled to hold talks with the Holy See Secretary of State, Cardinal Pietro Parolin, and the Secretary for Relations with States, Bishop Paul Richard Gallagher.

The talks are expected to focus on relations between the Holy See and Croatia, the situation in Southeast Europe, notably Bosnia and Herzegovina, climate change and “Laudato si”, the second encyclical of Pope Francis.

Milanovic is also expected to visit the Pontifical Croatian College of St. Jerome.

This is Milanovic’s second visit to the Holy See. The first visit took place in 2012 when he, as prime minister met with the then pope Benedict XVI.