Trading house Itochu Corp. said Friday it has agreed to buy a 10.3 percent stake in Australian uranium explorer Extract Resources Ltd. to benefit from global demand growth for the fuel.

The acquisition, which must be approved by Australia's Foreign Investment Review Board, will make Itochu the third-biggest shareholder of Extract Resources after Kalahari Uranium Ltd. and Rio Tinto Ltd., the trader said in a faxed statement.

The deal marks Itochu's second investment in four months in a uranium company with assets in Namibia after it bought 15 percent of Kalahari Minerals PLC in March. Itochu, which sells 4,000 tons of uranium year, plans to boost its nuclear fuel business, it said.

Extract's uranium projects in Namibia include the Rossing deposit, which supplies 8 percent of the world's needs, and the Langer Heinrich deposit, it said on its Web site.

Kalahari Uranium holds 41.1 percent of Extract and Rio Tinto has 14.2 percent, according to Bloomberg data. Itochu's 10 percent stake may be worth ¥15 billion, the Nikkei English News reported earlier Friday. Itochu spokesman Yasuhiro Terashita declined to disclose the value.