Pope Francis has arrived in Greek Island of Lesbos to show support for refugees trying to reach Europe.
The Pope is being met by Orthodox Patriarch Bartholomew. They will visit a camp for more than 3,000 people who are awaiting either processing of asylum claims or deportation to Turkey.
Lesbos has been a key entry point into Europe for migrants in the past year.
Thousands are now stuck on the island after last month’s deal between Europe and Turkey to try to ease the flow.
Pope Francis and Patriarch Bartholomew of Constantinople – the spiritual head of the world’s Orthodox Christians – will visit the Moria detention centre.
The Vatican insists that the Pope’s visit is purely humanitarian and religious in nature and should not be seen as a criticism of the deportations.
However, the Vatican official in charge of migrants, Cardinal Antonio Maria Veglio, has said the EU-Turkey plan treats migrants as merchandise and fails to recognise their dignity as human beings.
Pope Francis visited the Italian island of Lampedusa in 2013 to show similar support for migrants after dozens died trying to reach it.
The Pope was met at Lesbos Mytilene airport by Greek Prime Minister Alexis Tsipras, Patriarch Bartholomew and Archbishop of Athens Ieronimos II.
On the eve of the visit, one Syrian attempted to kill himself at the camp after being told he would be deported back to Turkey but was prevented by police.
Migrants later demonstrated, demanding better treatment and to stay in Europe.
The Greek authorities have not yet commented on the suicide attempt, which was confirmed by non-governmental organisations on the island.
The man was among four Syrians who have now appealed against their deportation orders.
However, some Syrians on Lesbos say they are terrified by the thought of returning to Turkey because of reports that hundreds of Syrians have been forcibly returned from Turkey to Syria.
Turkey has denied sending back any refugees against their will.
Refugees and migrants also complain of overcrowded conditions and a lack of food.