Japan, the world's third-biggest uranium consumer, will hold talks this week with Mongolia on jointly developing ore reserves as part of efforts to secure additional supplies of the nuclear fuel.

Hiroyuki Ishige, vice minister for trade, will lead a delegation of more than 50 government and company officials, a ministry official said on condition of anonymity because the trip hasn't been announced yet. The group will leave Wednesday and spend four days in Ulan Bator, the official said.

Japan is stepping up efforts to acquire uranium assets as competition for the fuel intensifies with China and India. China must construct two reactors a year to meet a goal of generating 4 percent of its power from atomic plants by 2020. India aims to increase nuclear output by one-third by that date after it won the right last month to buy technology, equipment and fuel from the 45-nation Nuclear Suppliers Group, ending a 34-year ban.

"The development of new uranium mines is vital as concerns are growing that production at several existing mines may start rapidly declining from 2020 onward," said Yuji Tanoue, head of Trade Tech in Tokyo, a nuclear-fuel consulting firm.

Mongolia has 62,000 tons of proven uranium reserves, or 1 percent of the world's total, according to the Japan Oil, Gas and Metals National Corp. The country has untapped areas that may contain as much as 1.39 million tons, which would make it the world's largest source of the ore, the group says.

Japan imports 9,000 tons of uranium a year, with 60 percent coming from Canada and Australia, according to the country's Federation of Electric Power Companies. In the past few years, Japan has agreed on joint uranium mine projects with Kazakhstan and Uzbekistan.