A.P. Moller-Maersk (MAERSKb.CO) is in talks to buy a portfolio of North Sea assets from Royal Dutch Shell (RDSa.L) as the Danish group considers adding scale to its oil and gas business ahead of a planned spin off, banking sources said. Maersk announced on Thursday a major overhaul that will see it focus on its core transport and logistics businesses, while looking at options for its energy division within 24 months that could include a joint venture, merger or listing. Maersk has said over the past year that it planned to invest several billions of dollars to expand its oil operations, although it is now likely to face bigger financial pressures given a rout in earnings from shipping, weak oil prices and the loss of a major oil contract in Qatar.

Maersk Oil has held talks in recent weeks about buying a large part of the North Sea portfolio that Shell is seeking to sell as part of a three-year, $30 billion divestment plan following its purchase of BG Group earlier this year, banking sources involved in the talks told Reuters. The assets under discussion are valued at around $2 billion, they added. Shell and Maersk Oil declined to comment. Although the aging UK North Sea is considered a relatively costly oil region, Maersk - which already has assets there - believes it can reduce the costs of running Shell's fields as well as the costs of dismantling and cleaning up assets nearing the end of their production lives, the sources said. Explaining Maersk's options for its energy business, one source with knowledge of the process said: "They could look to bulk it up potentially with merger combinations before an exit - the key is to make it attractive to get the value they want." Maersk Oil is currently developing the Culzean gas field which is expected to start production in 2019 and which could supply up to 5 percent of Britain's gas demand. The division produces around 500,000 barrels per day of oil and gas equivalent around the world, according to its website. Barclays analysts estimate

Maersk Oil would currently have a market value of around $4.7 billion as a standalone business. Maersk Oil has suffered a series of setbacks, first and foremost when Qatar chose not to extend its 25-year license to operate the giant Al Shaheen field. Its plans to develop a huge offshore field in Angola also stalled as it struggled to reduce costs. In February, Maersk tumbled to a loss after writing down Maersk Oil's assets by $2.6 billion. Still, many of the division's assets are considered attractive, including its stake in Norway's giant Johan Sverdrup oil field development. "The energy-division is sort of cut off with a 'For sale' sign in the window," Sydbank analyst Morten Imsgard said. "Maersk Oil is a small player in a larger context, so there are many players big enough to take in Maersk Oil. Drilling is relatively large, but its competitors are under extreme financial pressure, so Maersk is less likely to find a sell-off opportunity there." (Additional reporting by Nikolaj Skydsgaard in Copenhagen; Editing by Mark Potter) Crew members look out from the container ship, the MV Maersk Mc-Kinney Moller, as it berths during its maiden port of call at a PSA International port terminal in Singapore September 27, 2013. REUTERS/Edgar Su/File Photo