Oil behind China's UN Peacekeeping troop deployment to South Sudan

China's historic decision to deploy 700 troops to South Sudan as part of a UN peacekeeping force was prompted by a giant Chinese oil company signing of a new oil production deal with the East African state, according to an expert on oil in the region.

On the same day as the deployment was announced, the state-owned China National Petroleum Corporation announced a new deal had been signed with the South Sudan government for "stabilising and increasing crude output".

Chinese state news agency Xinhua reported that 180 troops would fly to the South Sudan next month, followed the rest of the battalion in March.

Recent heavy fighting between government forces and rebel groups in the country have cut oil production by almost a third, leading to growing concern in China, which is heavily dependent on South Sudanese oil.

In the 1990s, China invested billions in developing oil production in Sudan. Securing oil interests in the country is the reason for the UN peacekeeping troop deployment, stated author Luke Patey.

The deployment "runs parallel with its interest in ensuring billions of its oil investments in South Sudan stay out of harm's way," he told the New York Times.

Patey is the author of The New Kings of Crude: China, India and the Global Struggle for Oil in Sudan and South Sudan.

"China's concern regarding South Sudan is not energy security per se, but rather a corporate investment from a major Chinese national oil company in jeopardy," he said.

Debt repayments by Sudan, where China has also invested heavily in oil production, are to be rescheduled, Beijing announced.

The Chinese battalion will be equipped with drones, armoured infantry carriers, anti-tank missiles and mortars, reported Xinhua.

The UN currently has more than 11,000 peacekeepers in South Sudan, which became independent after breaking away from Sudan in 2011.

Riek Machar, the sacked former deputy of South Sudan's president Salva Kiiir is allied with rebel forces, which are trying to overthrow the government.