MOSCOW (Reuters) -- The world's top aluminum firm, Russia's United Company RUSAL, which is buying a blocking stake in metals giant Norilsk Nickel, said on Tuesday it wanted to purchase another 2 percent stake in the company.

“The official letter stating UC RUSAL's intention to buy 2 percent stake in Norilsk Nickel was sent to the CEO of KM-Invest on December 24, 2007,” RUSAL said in statement.
KM-Invest manages assets worth $11 billion-$14.7 billion belonging to tycoons Vladimir Potanin and Mikhail Prokhorov, who are in a complicated process of dividing their assets.
Last week the board of KM-Invest approved by a majority vote the sale of 2 percent of Norilsk and a 7.4 percent stake in Russia's top gold Producer Polyus.
Prokhorov's representatives on the board voted against the sale. Following the vote Prokhorov offered to buy Potanin's stakes in companies owned by KM-Invest, or to sell him his own at unspecified terms.
If the proposal were not accepted, Prokhorov said he would demand a liquidation of the firm at an extraordinary shareholders' meeting to be held no later than Jan. 21, 2008.
RUSAL said on Friday it would buy the strategic 25 percent stake in Norilsk Nickel from Prokhorov's Onexim Group, in a first step towards a full-scale takeover that would create a globally competitive Russian metals and mining major.
UC RUSAL accounts for about 12 percent of global production of aluminum and 15 percent of intermediate product alumina respectively.
It was founded in March 2007 through the merger of Russia's top aluminum producer RUSAL with its smaller rival SUAL and alumina assets of commodities trader Glencore.
Norilsk is the world's largest producer of nickel and platinum group metal palladium.