Mitsui & Co. Ltd (8031.TO) said Monday it expects to shoulder part of the costs stemming from the massive oil spill in the U.S. Gulf of Mexico

  (Adds Mitsui comments, background, insurance details)
  TOKYO (Dow Jones)--Japanese trading company Mitsui & Co. Ltd (8031.TO) said Monday it expects to shoulder part of the  costs stemming from the massive oil spill in the U.S. Gulf of Mexico, although it is difficult at this point to be  specific on numbers.
  "We will have to carry part of it as a stake holder," said a spokesman of Mitsui & Co. "But specifics like the
percentage and the total amount are unclear" because there are parties involved who are not shareholders (in the leaking  well) and as the leak is still ongoing, he noted. The official was responding to questions about the failure of oil field operator BP PLC's (BP) weekend efforts to plug the estimated 12,000 to 19,000 barrels a day of crude oil spewing into the Gulf of Mexico from a broken pipe 1,500 meters under the water.
  The Japanese trading company's unit Mitsui Oil Exploration Co. has a 10% stake in the offshore oil block from which the oil is leaking. Mitsui & Co has diversified interests in oil and gas, metals, power generation, chemicals and  transport.
  U.S. oil company Anadarko Petroleum Corp. (APC) has a 25% stake in the Gulf of Mexico block.
  Other companies, including oil field rig operator Transocean Ltd. (RIG) and oil field services company Halliburton Co.  (HAL), which performed cementing work on the well which ruptured April 20, have also been collaborating in efforts to contain the flow and to find out what happened.
  The Tokyo-based company hasn't been having a good time recently--on May 7 it said its net profit slid to Y149.72 billion from Y177.61 billion a year earlier, while revenue sagged 29% to Y9.358 trillion from Y13.125 trillion, although at the time it forecast a sharp recovery in net profits and revenues for the current year.
  The company's share price hasn't been hard hit, though--in the past three weeks its share price has fallen 3.9% while  the wider Nikkei 225 index has dropped 8.7%.
  On Sunday, BP said it would try to contain the oil flow with a new type of cap that would siphon oil to the surface  rather than by plugging the well, but the operation could initially increase flows and had never been tried before in  such deep water.
  Mitsui Oil Exploration has not sent staff to the disaster area, but it is ready to do so upon request, the Mitsui & Co. spokesman said. Mitsui Oil Exploration insurance contracts may cover the spill and collateral damage to third parties to a maximum of  $45 million, the Mitsui & Co. spokesman said.
  "This will definitely be one of the worst oil spill cases known in the industry's history," said Hidetoshi Shioda,
analyst with Mizuho Securities Co.  It may take years to settle the total cost, including compensation to industries like fisheries and tourism, and to  work out how to divide the costs, Shioda noted.
  "It is likely that Mitsui & Co. will build reserves for future costs in this fiscal year's earnings" started in April,
and book these as an extraordinary item, Shioda added.
  Mitsui & Co. holds 70% of Mitsui Oil Exploration, while Japan's Ministry of Economy, Trade and Industry owns 20%. The  reminder is held by several other Japanese companies.
  The company's oil exploration and production business is focused mainly in the Middle East, South East Asia and  Australia.
  -By Mari Iwata, Dow Jones Newswires; 813-6269-2798; mari.iwata@dowjones.com