China has begun deploying 700 soldiers to a United Nations (UN) peacekeeping force in South Sudan to protect oil fields and Chinese workers amid a rebellion in the African country, The Wall Street Journal reported.

The newspaper quoted a spokesman for South Sudan's president as saying on Tuesday that the airlift of a Chinese infantry battalion to the South Sudanese states of Unity and Upper Nile was expected to take several days.

China is the biggest investor in South Sudan's oil industry.

UN officials have previously said it would be the first time China had contributed a battalion to a UN peacekeeping mission. Last year China sent a smaller "protection unit" to join a UN mission in Mali.

China has played an unusually active diplomatic role in South Sudan. Beijing last month pressed South Sudan over renewed violence in the oil-rich state, demanding an immediate ceasefire and political dialogue in the country.

Under its mandate, UN peacekeepers are allowed to use "all necessary means" to protect civilians at oil installations, The Wall Street Journal said. If attacked, the Chinese soldiers are "combat ready and can fight back", the South Sudan presidential spokesman, Ateny Wek Ateny, said.

Chinese officials have been in regular contact with Western diplomats to help African mediators push for a halt to the fighting in South Sudan. China has pushed rival factions loyal to President Salva Kiir and rebel leader Riek Machar to talk.

-Reuters-