Chinese state oil company CNPC said it was evacuating workers from South Sudan because of political violence that has left hundreds dead.
"We are arranging the orderly evacuation of our workers, but I can't tell the evacuation destination or how many workers are being flown out," a spokesman for China National Petroleum Corp, one of the biggest investors in the country's oil industry, said.
Xinhua reported that CNPC was making arrangements to evacuate 32 Chinese workers from the oilfield where they work to the capital, Juba.
Foreign ministry spokeswoman Hua Chunying said that all Chinese in the country were safe, but some oil companies were temporarily shutting down their operations in light of the situation there.
Xinhua said an oilfield in the northern part of South Sudan, operated by a consortium of Indian, Malaysian and South Sudanese companies, was caught up in unrest on Thursday that killed 14 South Sudanese oil workers.
Earlier, a senior official at the Greater Nile Petroleum Operating Company, one of two consortiums in South Sudan in which CNPC is a major shareholder, said at least five South Sudanese workers had been killed after attackers stormed their compound in the key Unity oilfield on Wednesday night.
It was not clear if they were referring to the same or separate attacks or if the deaths was linked to rebel battles with government troops following an alleged coup attempt against South Sudanese President Salva Kiir, which has left at least 500 people dead.
Oil production forms over 95 per cent of South Sudan's fledgling economy, and any attack targeting the crucial installations raises fears for the stability of the vital industry.
A United Nations official reported on Thursday that about 200 oil workers who sought refuge at a UN base in Unity state were expected to be evacuated by their employers, without naming the companies involved.
Meanwhile, African diplomats made a push for peace as fighting spread across the world's youngest nation, and US President Barack Obama warned South Sudan was on the brink of civil war.
"Recent fighting threatens to plunge South Sudan back into the dark days of its past," he said. "South Sudan stands at the precipice."
South Sudan's numerous ethnic groups have battled each other for decades, but for years their animosity had a focus in hatred of the government in Khartoum, then, as now, the capital of Sudan. When the south gained independence in 2011, the groups' common enemy receded.
On Thursday, armed youths breached a UN compound in Jonglei state, causing an unknown number of casualties.
"Unfortunately, just this very morning such militia groups have targeted and killed three soldiers from India in South Sudan," India's UN ambassador, Asoke Mukerji, told a UN meeting on peacekeeping. It was the first announcement of UN deaths in the upsurge of violence.
South Sudan's government declared that its security forces "are in absolute control of the situation", but admitted on Thursday that the central government had lost control of Bor, the capital of Unity, the country's largest and most populous state, where barrages of gunfire were reported.
"The situation in South Sudan can be best described as tense and fragile. If it is not contained, it could lead to ethnic cleansing," said Choul Laam, a top official with the ruling Sudan People's Liberation Movement, who spoke in Nairobi, Kenya.
Violence broke out on Sunday when the presidential guard splintered along ethnic lines.
Agence France-Presse, Reuters, Associated Press