Updated

A South Sudanese official said Monday that his government expects Uganda to play a substantial role in resolving the border conflict that has at times threatened to plunge South Sudan and Sudan into a full-scale war.

Barnaba Marial Benjamin, South Sudan's information minister, told a news conference in Kampala that Uganda is obligated to stand by South Sudan as it pursues an end to a conflict that has shut down the country's oil production and left it exposed to bombs dropped by Sudan's air force.

"Uganda has a responsibility to stand by us," he said. "Uganda has a role to play. They have got to look after this baby."

South Sudan last year voted to became the world's youngest nation, breaking off from Sudan after decades of war.

Uganda actively supported the Sudan People's Liberation Army, the rebel movement that is now South Sudan's military, and then played an important role in negotiations that led to a comprehensive peace agreement between the north and the south in 2005.

Gen. Aronda Nyakairima, overall commander of the Ugandan military, told a meeting of regional military chiefs in Kampala last month that the elusive rebel leader Joseph Kony had re-established contact with his supporters in Sudan and that Uganda would back the south if the border conflict between Sudan and South Sudan escalated into war.

He said Uganda would "not sit back" and watch if war broke out between the two Sudans.

Ugandan officials now say Kony, the fugitive leader of the brutal Lord's Resistance Army, is hiding in Sudan. They say this information was obtained from a captured LRA rebel who wore a new uniform supplied by the Sudanese army.

Nyakairima has not repeated the Sudan comments in public, and Ugandan diplomats have been trying to clarify them without actually disowning them.

An official at Uganda's Ministry of Foreign Affairs said Kampala must collaborate with other regional governments, such as in Kenya and Ethiopia, that have traditionally backed South Sudan's full independence from Sudan.

"As a guarantor (of the peace process), you are part of the solution and you remain engaged," said James Mugume, permanent secretary at the Ministry of Foreign Affairs. "The (South Sudanese) minister is right to say Uganda is part of the solution. When he says Uganda has a responsibility he is not lying."

Ugandan President Yoweri Museveni has long accused Khartoum of displaying a racist attitude toward the south. Last November, in an emotional press conference with South Sudan President Salva Kiir in Kampala, Museveni said Uganda would back South Sudan in the event the two Sudans went to war.

Museveni said at the time that Sudanese President Omar-al Bashir "must henceforth stop organizing aggression against the south."

Sudan is predominantly Arab while the south is predominantly black.

Last month South Sudan and Sudan appeared to be on the brink of all-out war after South Sudan captured the oil-rich town of Heglig. Sudan later said its forces pushed South Sudan out of Heglig. South Sudan claimed it was a voluntary retreat.

International pressure from the U.N. Security Council and African Union appears to have helped calm tensions on the border.