The Pope is due to arrive in Jordan at the start of a three-day visit to the Middle East which will also take him to Israel and the Palestinian territories.
Pope Francis will first travel to Amman, where he will celebrate Mass in a stadium, and later meet Syrian refugees.
The official purpose of the visit is to improve ties with the Orthodox Church.
But correspondents say many will expect Pope Francis to use his influence to try to ease tensions in the region. BBC