Anglo-Dutch oil group Shell has started pumping crude from a new unit in its massive offshore Bonga oil field in Nigeria, raising output by 50,000 barrels per day.
"Bonga Phase 3 is an expansion of the Bonga Main development, with peak production expected to be some 50,000 barrels of oil equivalent," the company said in a statement on Monday.
"This new start-up is another important milestone for Bonga, adding valuable new production to this major facility," said Andrew Brown, Shell's upstream international director.
Shell said the new output would be transported through existing pipelines to the Bonga floating production storage and offloading (FPSO) facility.
The FPSO has the capacity to produce more than 200,000 barrels of oil a day, it said.
The Bonga field, which began producing oil and gas in 2005, was Nigeria's first deep-water development in depths of more than 1000 metres.
Bonga has produced over 600 million barrels of oil to date.
It was built by Shell to overcome the risks of unrest and sabotage of pipelines associated with onshore facilities in the restive oil-producing Niger delta region.
Shell is a leading oil operator in Nigeria, Africa's largest producer with a daily output of some two million barrels per day.