BEIRUT (AFP) - A group of nuns kidnapped from a Syrian town in December were expected to be released, thanks to Lebanese-Qatari mediation, a monitoring group and Lebanese media reports said on Sunday.

The 13 nuns and three maids were kidnapped from the famed Christian hamlet of Maalula and taken to the nearby Syrian rebel town of Yabrud, where they have been held by Al-Qaeda affiliate Al-Nusra Front.

The reports come after Syria's authorities called journalists to the war-torn country's border with Lebanon, presumably to witness the handover of the nuns.

By the late afternoon, however, the women had not yet been escorted to the border, according to an AFP on the Syrian side of the frontier.

"Thirteen nuns and three monastery orphanage workers from Maalula are expected to be handed over shortly," the Syrian Observatory for Human Rights said.

The expected release was being negotiated by Lebanon's General Security agency chief Abbas Ibrahim and Qatar's intelligence chief Ghanem al-Kubeissi, who arrived in Lebanon on Saturday, according to the official National News Agency (NNA).

"We cannot confirm for now whether they have been handed over to Ibrahim and the Qatari intelligence chief," said Observatory director Rami Abdel Rahman.

The Orthodox church was also unable to confirm the release of the nuns who are Syrian and Lebanese.

The Britain-based Observatory, meanwhile, said the release was being negotiated in exchange for the liberation of 150 women prisoners held by President Bashar al-Assad's regime.

Lebanese media said the women were expected to be escorted to Arsal in eastern Lebanon, a town whose population is sympathetic towards Syria's rebels, from where they would be taken to the official Masnaa border crossing with Syria.

Last year, Qatar and Lebanon's Ibrahim played a leading role in securing the release of a group of Lebanese Shiite pilgrims held by Syrian rebels in northern Syria.

Qatar has been a key backer of Syria's revolt.

The nuns were kidnapped on Dec 3 amid fighting for the ancient village of Maalula, which is currently in rebel hands.