British Energy and Climate Change Secretary Ed Davey said Friday that Norwegian energy major Statoil was given consent to drill in the Mariner heavy oil field in the North Sea.
"Mariner will be one of the biggest projects ever in the North Sea and the $7.1 billion commitment over 40 years from Statoil is a vote of confidence in the future of UK oil and gas," Davey said in a statement. "Importantly, unlocking heavy oil production marks a new chapter in development, opening the potential for 5 percent of our oil reserves."
Discovered in the early 1980s, production at Mariner was delayed because of technological limitations in extracting the denser type of oil.
The British government expects the field to eventually produce around 55,000 barrels of oil per day, about 5 percent of the country's current production.
Statoil said it aims to start production in 2017. Peak production should be achieved by 2020.
"The North Sea is a core area for Statoil and we look forward to taking a leading role in further developing also the U.K. part of this basin," Statoil President and Chief Executive Officer Helge Lund said in a statement.