By Daniel Gilbert 

BP PLC is selling stakes in four Alaska North Slope oil fields to Hilcorp Energy Co., ratcheting down its investment in a region it helped pioneer as the oil company seeks to raise cash.

The London-based company said on Tuesday it would sell interests to the closely held Houston-based company. The companies didn't release financial terms of the deal, but a BP spokesman said the company "secured good value for these interests."

Hilcorp called the purchase a major acquisition for the company--its third in Alaska since 2012.

"Our ability to bring new life to mature basins is a great fit for these assets," John Barnes, a senior vice president at Hilcorp, said in a statement.

For BP, long a major player in Alaska, the sale marks a narrowing focus as it seeks to raise $10 billion in cash, with most funds earmarked to buy back shares. BP's stock plunged after the Deepwater Horizon disaster and oil spill in April 2010 and has yet to recover its value from before the deadly explosion. The company will focus its efforts on tapping crude oil from Prudhoe Bay and exporting natural gas, Lamar McKay, head of BP's oil and gas development business, said.

"This agreement will help build a more competitive and sustainable business for BP in Alaska," Mr. McKay said.

BP is selling all of its interests in the Endicott and Northstar fields, and 50% of its stake in the Liberty and Milne Point fields. The company is also selling its interest in the pipelines that ship oil and gas from those properties.

Hilcorp has expanded its holdings in Alaska in recent years, buying properties in Cook Inlet from Marathon Oil Corp. and Chevron Corp.

Maria Armental contributed to this article.

Write to Daniel Gilbert at daniel.gilbert@wsj.com

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