AMSTERDAM, Netherlands (AP) — Royal Dutch Shell PLC reported a 21 percent gain in fourth-quarter earnings yesterday, buoyed in part by high energy prices and the sale of some operations.Net profit came to $5.28 billion, up from $4.37 billion. But excluding divestitures and other one-time items, Shell’s earnings from oil production fell 3 percent, while fourth-quarter sales were flat at $75.5 billion.

The company also said it had taken important steps to bulk up its proven reserves, which were revealed to have been inflated in a 2004 accounting scandal.

Shell said it expected to have added about 2 billion barrels of oil to its proven reserves in 2006, or 700 million barrels more than the 1.3 billion it pumped, when calculated under US accounting rules.

The company said it added twice as much as it pumped when taking into account oil-rich sands, which new technologies and higher crude prices are making possible to extract at a profit, but which cannot be counted as proven reserves under current rules. Shell said 30 million barrels were already pumped from oil sands this year, and chief executive Jeroen van der Veer said the company’s “exploration strategy is paying off.”

Shell has been desperately seeking to secure new sources of oil since it was forced to cut proven reserves by nearly a third amid the scandal.

In addition, the company must make up ground it lost in December, when Russia’s state-owned OAO Gazprom grabbed control of a massive oil project on Sakhalin island, forcing Shell to cut its 55 percent stake in the project to 27.5 percent in exchange for a $4.1 billion payment. Shell said yesterday that deal will result in a reserve cut of 400 million barrels in 2007.

Van der Veer said the company’s short-term outlook “continues to be impacted by security problems in Nigeria, affecting 2007 production and future growth.”

Shell said total fourth-quarter production was 3.65 million barrels of oil per day, up from 3.5 million a year ago, better than analysts expected.

The average selling price was $54.65 per barrel, up from $52.77 in the fourth quarter of 2005, but down significantly from $65.13 in the third quarter of 2006 — a decline that likely will only begin to impact quarterly earnings a year from now.

The company is pumping more oil from its offshore facilities in Nigeria, but overall production there fell by 191,000 barrels per day from a year ago due to armed attacks on its operations by local people who want a larger cut of oil proceeds.

“We now expect overall oil and gas production in 2007 to be in the range of 3.3-3.5 million barrels of oil per day, in the event that Nigerian volumes remain deferred for the rest of the year,” Van der Veer said.

“The reduced Nigeria outlook, and divestments including the dilution of our stake in Sakhalin II, mean we expect only modest production growth to the end of the decade.”

He predicted the company will increase production on average by 1 percent to 2 percent annually through 2010 and after that by 2 percent to 3 percent.

Shell said it expects a total of $22 billion to $23 billion in net capital expenditures in 2007, up from $21 billion in 2006 — the bulk going toward production projects under development.