SHANGHAI, CHINA -- The state-owned Chinese energy company China National Offshore Oil Corporation (CNOOC) announced on Monday that it has signed a definitive agreement to purchase a 45 percent stake in a Nigerian oil and gas field.

CNOOC will pay a reported $2.28 billion for a 45 percent interest in an offshore oil license it acquired from South Atlantic Petroleum of Nigeria. The field is believed to have more than one billion barrels of oil, making it one of the world’s largest oil and natural gas basins.

This is not CNOOC’s first foray into bidding for high-priced energy assets. Last year it offered more than $18 billion for Unocal.

“The purchase of this interest helps CNOOC gain access to an oil and gas field of huge interest and upside potential, located in one of the world’s largest oil and gas basins,” said CNOOC Chairman and Chief Executive Fu Chengyu in a prepared statement. “This transaction is perfectly aligned with CNOOC’s long term strategy of achieving growth through the exploration and development of offshore fields and achieving geographic diversification of the company’s portfolio.”

Last month, the Oil and Natural Gas Corporation of India reached a tentative deal to purchase the field for about $2 billion. However, India’s cabinet blocked the deal over concerns about the transparency of Nigerian ownership, according to Bloomberg News.

As demand for oil ramps up in energy-hungry countries like India and China, which currently imports about 40 percent of its oil, energy analysts expect that additional deals are likely. 

The deal requires the approval of the Chinese and Nigerian governments.