UPDATE 1-Areva sales slip as mining cushions Fukushima blow

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PARIS Jan 26 (Reuters) - French nuclear group Areva posted a 2.6 percent fall in 2011 sales as strength in its mining unit helped cushion declines in its core reactor businesses as it restructured following the nuclear disaster in Japan.

Revenues at the world's biggest maker of nuclear reactors, which in December disclosed a massive write-down tied to three of its African mines, reached 8.87 billion euros ($11.67 billion), with the reactors and services unit showing a 3.6 percent drop.

Fourth-quarter revenue at the company, which has lately been embroiled in a controversy over former Chief Executive Anne Lauvergeon's role in a disastrous mining acquisition, totalled 2.922 billion euros, down 0.5 percent.

Lauvergeon's successor Luc Oursel said in a statement the limited nature of the drop in revenues despite the jitters caused by Fukushima "illustrates the robustness of Areva's integrated business model." Areva earns a large part of its sales from the upkeep of existing facilities.

The order backlog rose 3.1 percent to 45.6 billion euros as of Dec. 31, Areva added. Since the nuclear disaster at Japan's Fukushima power plant in March, order cancellations have been 464 million euros.

Reactors and services, which designs and builds nuclear reactors and is Areva's biggest division, saw revenues slide to 3.26 billion euros as fewer engineering studies were undertaken in the United States.

Areva has been grappling with construction delays at two of its new-generation EPR reactors, while the Fukushima crisis has sparked a global debate about the future of nuclear power and led some governments to review their energy mix.

On top of that, Areva, the world's biggest uranium mining producer, is bogged down by the $2.5 billion acquisition of Canada's UraMin in 2007 and allegations of spying on the long-serving Lauvergeon.

Despite the dark cloud of Uramin, Areva's mining unit had the most robust sales growth of any unit aside from its much smaller renewable energy business, which nearly doubled.

Mining revenue rose 18 percent to 1.29 billion euros, helped by an increase in uranium prices.

($1 = 0.7601 euros) (Reporting By Christian Plumb and Caroline Jacobs; Editing by Lionel Laurent)