Pope Francis nuns Syria
Pope Francis called for prayers for Mother Superior Pelagia Sayyaf and other nuns abducted in Maaloula, Syria (Reuters)

Pope Francis called for prayers for a group of nuns who were abducted by Islamist rebels in southwest Syria.

Mother Superior Pelagia Sayyaf and 11 nuns were kidnapped from St Tecla Orthodox monastery in the predominantly Christian town of Maaloula as it was overrun by rebels.

"I invite everyone to pray for the sisters of the Greek Orthodox monastery of St Tecla in Maaloula, Syria, who were taken by force by armed men two days ago," Francis said during the general audience at the Vatican.

"Let us pray for these nuns, these sisters and for all those who have been abducted during the ongoing conflict. Let us continue to pray and to work together for peace."

In November Francis had voiced his concerns for the safety of Christians living in Syria.

His appeal follows that of Syria's Greek Orthodox Patriarch, John Yazigi, who urged kidnappers to release the nuns, adding that some orphans who were in the foster care of the sisters had also been taken hostage.

It is not clear if the 12 nuns have been kidnapped for ransom or were forcibly evacuated from the convent for fighting purposes.

Maaloula, which was a major tourist attraction and a pilgrimage site for Christians and Muslims alike before the war, was captured by rebel groups, including the al-Qaida-linked Jabhat al-Nusra.

A Syrian opposition activist going by the name Amer claimed the nuns were taken away for their own safety due to intense shelling over the city.

Amer said the nuns were "being taken care of" by a Christian family in the nearby rebel-held city of Yabroud.

Jihadist rebels have been known to kidnap Christian priests in the past. Jesuit missionary Paolo Dall'Oglio, 59, was abducted in July in northeastern Syria and his whereabouts remain unknown.

St Tecla's mother superior also voiced her support for Bashar al-Assad in the past.

Shortly after the abduction a message was received by the mother superior of nearby Christian convent of Saidnaya, Febronia Nabhan, that the sisters were "fine and safe".

Later, Nabhan's deputy, Stephanie Haddad, said she also spoke to some of the abducted nuns and insisted they were being held against their will.