Russia will seek to sell off 10.9 percent of diamond exporter Alrosa as it presses its bid to prop up the ruble amid slumping oil prices, a report said Wednesday.The Russian government in December last year ordered state-controlled exporters to sell part of their foreign currency holdings to try to marshall billions of dollars. The government has now decided to sell 10.9 percent of Alrosa's shares on the Russian stock exchange, where the mining group is already listed, Vedomosti daily reported, citing officials and industry sources.At the moment, 44 percent of the company is owned by the federal state and 25 percent by the far northeast region of Yakutia. Sixteen percent of the company's shares have been listed on the stock market since 2013, but sales have been dismal. The sale of another 10.9 percent of the company's share.