(Adds details, background, changes dateline, previous BEIJING)
By Abdoulaye Massalatchi
NIAMEY, June 3 (Reuters) - China's state oil company has won a $5 billion deal to develop oil reserves in eastern Niger in the latest major Chinese investment to secure energy resources in Africa, officials from both countries said on Tuesday.
Under the agreement signed in Niamey late on Monday, China National Petroleum Corp (CNPC) agreed to bring into production within three years the large Agadem block, which has proven reserves so far of 324 million barrels, Niger's government said.
The top oil firm in China will also build a refinery with capacity of 20,000 barrels per day near the southern city of Zinder, and a 2,000-kilometre pipeline to export the oil.
The total estimated investment of $5 billion is China's biggest in the Sahel state, where Chinese companies are also involved in the exploration and development of uranium.
Niger, which is battling an insurgency by Tuareg led-rebels in its northern uranium zone, is among the world's top producers of the radioctive mineral used to fuel nuclear reactors.
CNPC's Agadem production sharing agreement extends China's role in sub-Saharan Africa's booming oil sector.
Besides Sudan, where China is the biggest investor, Chinese oil companies are also operating and exploring in Nigeria, Angola, Equatorial Guinea and Chad.
"Our government is firmly convinced that we've achieved a win-win contract for the benefit of the people of China and Niger," Niger's Mines and Energy Minister Mohamed Abdoulahi said at the contract signing ceremony.
"CNPC will respect its engagements and obligations," Ye Xiandeng, Vice-Preisdent of CNPC subsidiary CNODC, said.
The accord foresees the Chinese company drilling a minimum of 18 exploration wells over the next eight years, 11 of them within four years. The company also commits itself to carrying out nearly 4,000 km of seismic exploration in the Agadem block, located in the eastern Diffa region bordering with Chad.
SECURITY WORRIES
Niger's eastern Diffa region has been relatively unaffected by a year-old revolt by Tuareg-led rebels who mostly operate in the country's northern desert region of Agadez.
The rebels of the Niger Justice Movement (MNJ) are seeking more autonomy and a greater share of their northern region's wealth and in 2007 they briefly kidnapped an executive of a Chinese uranium company working there. He was later freed.
Leaders of the MNJ, which has recently suffered internal splits, have also warned Chinese oil and mining companies to leave or face attack. They accuse China of supplying arms and munitions to the Niger army in exchange for concessions.
While hailing the Agadem agreement, China's ambassador to Niger appealed for peace in the country.
"To develop a nation, you have to have security. Without security, you can't do anything," Chen Gonglai said.
CNPC is also exploring the Tenere and Bilma oil concessions in Niger.
In March, a Chinese oil industry official said China wanted up to 40 percent of its oil and gas imports to come from Africa in the next 5-10 years. China had invested some 30 billion dollars in Africa's oil and gas industries, he added.
In 2005, China was already importing more than 30 million tonnes of oil from Africa, about 30 percent of its total oil imports, and this was believed to have increased since. (For full Reuters Africa coverage and to have your say on the top issues, visit: http://africa.reuters.com/) (Additional reporting by Jim Bai in Beijing; writing by Pascal Fletcher; editing by James Jukwey)
