Nine Ugandan soldiers have been killed and 12 others wounded during a month fighting in South Sudan, the army said Tuesday, dismissing rebel claims to have killed scores.

Ugandan President Yoweri Museveni confirmed last week that troops had been killed during combat in the war-ravaged young nation in support of President Salva Kiir.

Formal peace talks between South Sudan's government and rebels are set to open Monday in the Ethiopian capital Addis Ababa, delegates and diplomats said.

The talks, brokered by the East African regional bloc IGAD and aimed at ending three weeks of unrest in South Sudan, are set to start at 3:00pm (1200 GMT), Ethiopian government spokesman Getachew Reda said.

An Ethiopian passenger was arrested at Rafik Hariri International Airport on Sunday for trying to smuggle drugs to Lebanon, the state-run National News Agency reported.

NNA said the airport customs found nine kilograms of khat, a traditional herbal stimulant drug, in the Ethiopian woman's suitcase.

South Sudan's warring parties on Saturday met in Addis Ababa for the first time since fighting erupted three weeks ago and formally opened talks to strike a ceasefire deal.

"South Sudan deserves peace and development not war," Ethiopian Foreign Minister Tedros Adhanom said at an opening ceremony attended by the government and rebel negotiating teams.

Face-to-face talks between warring parties in South Sudan have been delayed, government and rebel delegations said Saturday, dashing hopes of a swift ceasefire to end raging battles and risks of all-out civil war.

South Sudan Information Minister Michael Makuei, part of the delegation to the talks in Ethiopia's capital Addis Ababa, as well as rebel team spokesman Yohanis Musa Pouk, said the two sides would not meet Saturday until an agenda had been drafted by negotiators and agreed by both sides.

South Sudan's warring parties began negotiations Friday to end nearly three weeks of raging conflict which has left thousands feared dead and taken the world's youngest nation to the brink of all-out civil war.

Fighting intensified as the army moved on a key rebel-held town, even as government and rebel negotiating teams gathered at a luxury hotel in neighboring Ethiopia's capital Addis Ababa.

South Sudan's sacked vice president Riek Machar said Tuesday he was ready for peace talks with his estranged mentor President Salva Kiir to bring an end to deadly clashes across the country.

"Yes we are ready for talks. I have formed my delegation," he told Radio France Internationale (RFI), adding that the negotiations would likely be held in Ethiopia.

Israeli Mossad agents operating in Ethiopia in 1962 unwittingly trained Nelson Mandela in hand-to-hand combat, weaponry and sabotage, according to a document released by Israel's state archives.

A letter from a Mossad official to the foreign ministry, dated October 11, 1962 titled "THE BLACK PIMPERNEL" and released to the public on Sunday, recalls a conversation in which "we discussed a trainee in Ethiopia named David Mobasari, from Rhodesia".

Ethiopia has repatriated over 100,000 citizens from Saudi Arabia, Addis Ababa's foreign ministry said Thursday, following a violent crackdown against illegal immigrants in the oil-rich kingdom.

Ethiopian Foreign Minister Tedros Adhanom said that up to 50,000 more citizens are still expected to come home.

Sudan and Ethiopia on Wednesday were to inaugurate a cross-border electricity link which an analyst said aims to strengthen Khartoum-Addis Ababa ties as tensions persist with Egypt over a giant dam.

Ethiopian Prime Minister Hailemariam Desalegn would attend the ceremony in Sudan's eastern city of Gedaref, the official SUNA news agency reported.