Peace talks to end South Sudan's more than seven month-long civil war resumed Monday, with mediators warning rival leaders would face repercussions if fighting continued, amid warnings of looming famine.
The regional bloc brokering the talks, IGAD, has set an August 10 deadline for both sides to agree on a transitional government and implement a ceasefire.
The last round of peace talks between President Salva Kiir and his former deputy Riek Machar stalled in June with each side blaming the other for the failure.
"This session of negotiations must make progress, we must end the war," chief mediator Seyoum Mesfin said at the opening of talks in the Ethiopian capital.
"Any result to continue it will have serious consequences... those that insist on continued fighting must be held accountable."
The US and the EU have slapped sanctions on senior military leaders on both sides, and IGAD leaders have threatened measures if both sides continue to violate previous peace deals.
Thousands of people have been killed and over 1.5 million have fled more than seven months of fighting between government troops, mutinous soldiers and ragtag militia forces divided by tribe.
Aid agencies have warned of the likelihood of famine within weeks if fighting continues.
China's ambassador to Ethiopia and the African Union criticised talks for moving at a "snail's pace" and said the world was losing patience.
"The patience of the regional countries and the international community are being worn out because they haven't seen real results, they see only the looming famine and the continued suffering of the people there," said Xie Xiaoyan.
"It is high time to stop this," he added.
China, which has major investments in South Sudan's oil fields, has closely followed the talks since they started in January.
Fresh fighting in the strategic town Nasir last month broke a fragile ceasefire, the third since January.
On Monday, the government blamed rebel chief Machar of launching fresh attacks.
"Riek Machar and the SPLM-A in opposition should not waste any more time over military campaigns," said the head of the government delegation, Nhial Deng Nhial, referring to the rebel force.
Previous rounds of talks, held in luxury hotels in Addis Ababa, have already cost at least $17 million (12 million euros) but have yielded few results.