Lockheed said the move showed the Norwegian government's "trust and confidence" in the F-35 program, and pledged to work closely with the Norwegian government to accommodate and implement its revamped plans.

Lockheed is developing three variants of the radar-evading new fighter for the U.S. military and the eight partner countries that are helping fund its development: Britain, Norway, Canada, Denmark, Italy, Turkey, Australia and the Netherlands.

The U.S. Defense Department in February announced plans to postponed orders for 179 F-35 jets to save $15.1 billion over the next five years and allow more time for testing before production ramps up on the $382 billion program.

The U.S. move, part of a Pentagon drive to cut spending by $487 billion over the next decade, and budget pressure overseas have prompted some countries to rethink their own orders. Italy, for instance, cut its order by 41 planes to 90.

Norway's defense budget remains among the highest per capita in Europe, and on Friday, it released a white paper that called for a 7 percent increase in defense spending from 2013 to 2016, part of "a temporary strengthening ... dedicated to the purchase of Norway's new fleet of F-35 combat aircraft."

The paper said Norway aimed to buy 52 F-35 fighter jets, including four training planes, from 2015 through 2023 or 2024, a plan that would see initial funding flow to Lockheed in 2013.

The previous plan called for Norway to buy 48 planes from 2016 through 2020, according to a document prepared for the F-35 program office, with initial funding to begin in 2014.

Norway said stretching the orders over a longer period would give it greater flexibility and help spread out the cost more evenly. It said it was not revising its estimate for procurement cost of the planes, despite changes in orders by the United States and other countries that could drive the price higher.

The Norwegian statement noted that the country's parliament would be involved in each yearly acquisition of aircraft, and said the final six orders for production planes would be confirmed at a later stage.

The Pentagon's F-35 program office also welcomed the news from Norway and said it would continue to work closely with Norway's military on development of the F-35.

(Reporting By Andrea Shalal-Esa; Editing by Bob Burgdorfer)

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