Dana Petroleum is reported to have first oil flowing from its flagship Western Isles development.
The milestone moment for the development was said to have happened at 5.25pm on Wednesday night when the flare was lit.
The Dana-operated Western Isles Project is the development of two discovered oil fields called Harris and Barra in the northern North Sea, 160km east of the Shetlands and 12km west of Tern field.
It involves a subsea development tied back to a new build floating production, storage and offloading vessel (FPSO), which was built in China.
The 28,000tonne unit has a total capacity of 50,000 barrels per day.
The UK Government first gave approval for the project back in December 2012.
But the date for expected first oil was pushed back after it emerged that the price tag for the project had reached £1.4billion.
The development, in which operator Dana has a 76.92% stake, with Cieco owning 23.08%, was “reset” at the end of 2014, with a longer timeline and bigger budget.
Plateau production is expected to be around 40,000 boepd, adding more than 30,000 boepd to Dana’s UK production.
The estimated field life is 15 years.
A spokesman for Dana said: “Dana will be issuing a formal announcement in due course.”
The Western Isles Development Project is touted by the company as being “pivotal” to future growth.
It is the largest project currently being undertaken by the company and demonstrates Dana’s commitment to the North Sea.
It is also Dana’s first end-to-end exploration and production project.
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