South Sudan rebel chief Riek Machar questions government’s commitment to peace

South Sudan rebel chief Riek Machar said Thursday he is committed to the country's new peace deal, but criticised a government list of reservations undermining key parts of the accord.

Amid the threat of international sanctions, President Salva Kiir signed the peace accord on Wednesday at a ceremony in Juba, but listed key concerns including power sharing with rebels and the demilitarisation of the capital.

"This casts doubts towards his (Kiir's) commitment to the agreement," Machar told AFP on Thursday in the Ethiopian capital. Under the deal, Machar is expected to take the post of first vice-president.

"All of us have reservations, but we didn't taint our signature with reservations, because it would mean we are reopening the negotiations," said Machar, who had already signed the deal on August 17, adding that he remained "committed to implement it."

At least seven ceasefires have already been agreed and then shattered within days or even hours in South Sudan, which broke away from Sudan in 2011.

Many fear the rivals will be not be able to rein in forces on the ground, or sit together to share power in the capital Juba.

"We'll see. We have been sitting in the same room talking," Machar said. "Governing has rules that people follow, and with these rules we should be able to implement the agreement - and return the country back to peace and stability."

The government's 12-page document of 16 reservations however calls the rebel post of first vice-president a "humiliation" and a "reward for rebellion", and insists the job must be on an equal footing with the current vice-president, whose post remains.

But Machar said what mattered was the signed deal.

"The agreement has outlined what powers the president will exercise, and what powers the first vice-president will exercise, so it is clear," Machar said.

Two powerful rebel generals, Peter Gadet and Gathoth Gatkuoth, split from Machar earlier this month, accusing him of seeking power for himself. The government has said the split is a key reason they doubt the peace deal can be effective.

But Machar dismissed the division.

"They don't command any forces... I am the commander-in-chief not those two gentlemen," Machar said.