An Irish aid worker who was kidnapped in Sudan two months ago has contacted her family by telephone, raising hopes for her release.

Sharon Commins, 32, from Dublin, was kidnapped in the North Darfur town of Kutum along with a Ugandan colleague, Hilda Kawuki, on July 3, by an armed gang of men who entered the compound of the Irish aid agency GOAL.

"She spoke to her family on Thursday. It was her first opportunity to speak to her family," a Foreign Ministry spokesman said. "The family have asked that we respect their privacy."

The spokesman described the phone call as a "hopeful sign", while saying: "We don't want to raise expectations too much. Our inter-agency team remains in Sudan and the minister is in continuing contact with the Sudanese Government."

Ireland's Foreign Minister, Micheál Martin, expressed cautious optimism after a two-day visit to Khartoum last weekend, stressing to the authorities the urgency of action to have the two women freed.

The Sudanese minister for humanitarian affairs, Abdul Bagi al-Jailani, who has been overseeing negotiations for the women's release, said that he was heartened by the phone call.

"We have many channels on the ground to try to secure the women's release. The phone call came about as a result of a new channel," he told the Irish Times.

Jailani emphasised that the Sudanese authorities remain optimistic that the women will be freed — possibly around September 19, when Muslims in Sudan celebrate the end of the holy month of Ramadan.

The two aid workers' ordeal is the longest endured by foreign aid staff in Darfur since the conflict erupted in the western region in early 2003. Until March no aid worker had been held in Darfur for longer than 24 hours.

In March the International Criminal Court issued an arrest warrant for President Omar al-Beshir for alleged war crimes in Darfur, triggering a sharp deterioration in Sudan's relations with foreign relief organisations.

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