The chief executive of OMV, Gerhard Roiss, told CNBC that its purchase of the fields was part of a strategy to move "upstream," to increase oil exploration and production and to increase returns.
"In September 2011, [I presented our strategy] saying we wanted to go upstream and reduce our asset base in downstream [operations after the production phase] because we see that there's much higher return in the upstream area."
Statoil sold 19 percent of Gullfaks, 24 percent of Gudrun and agreed optional cooperation in 11 of Statoil's exploration licences in the Norwegian North Sea, West of Shetland and the Faroe Islands. Gullfaks, onstream since 1986, is one of Statoil's most mature projects and Gudrun is one of its newest, with production set to start in 2012.
OMV had operated in Norway since 2006, Roiss said, and had steadily boosted its presence in the country's oil industry. He said the deal was meant to give OMV a "balanced portfolio" in production and development and a long-term position in the country.
The deal, which includes a firm $2.65 billion, could increase by a further $500 million to cover additional investments, freeing cash for Statoil as it spends $19 billion on bringing a string of new discoveries into production.
(Read more: Norway's oil fund to become active investor)
"Through this transaction, Statoil captures value created through asset development and unlocks capital for investment in high-return projects in core areas," Statoil Chief Executive Helge Lund said.
However, it will also make it more difficult for Statoil to reach its target of lifting production to 2.5 million barrels of oil equivalents (boe) by 2020, from about 2 million last year.
For OMV, meanwhile, the deal lifts its proven and probable reserves by about 320 million boe, or about 19 percent, and will boost production by about 40,000 barrels in 2014 and almost 60,000 barrels in 2016.
(Read more: How Norway could become a victim of its own success)
OMV, which produced about 297,000 boe per day in the second quarter, targets production of 350,000 boe per day by 2016.
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