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By Taiga Uranaka
TOKYO, June 5 (Reuters) - Japan's Nikkei average fell 0.7 percent on Thursday, with trading houses such as Mitsubishi Corp <8058.T> down on a fall in oil prices.
Softbank Corp <9984.T> jumped, cushioning the overall market's fall, after Japan's No.3 mobile phone carrier said it would start selling Apple Inc's <AAPL.O> popular iPhone in Japan. [
]Market analysts said the Tokyo market was taking a breather after recent sharp gains, with overnight losses in the Dow Jones industrial average <
> prompting investors to lock in profits."There are some alarming factors, such as possible downgrades of monolines," said Katsuhiko Kodama, a senior strategist at Toyo Securities, referring to U.S. bond insurers.
Moody's Investors Service said it is likely to cut the top credit ratings of the bond insurance arms of MBIA Inc <MBI.N> and Ambac Financial Group <ABK.N> on concerns about mortage-related losses and limited business prospects. [
]Financial shares fell, with Japan's top lender Mitsubishi UFJ Financial Group <8306.T> down 1.1 percent at 1,137 yen.
The benchmark Nikkei <
> ended the morning down 99.78 points at 14,335.79. The broader TOPIX index < > lost 0.5 percent to 1,423.29.Mitsubishi lost 3.3 percent to 3,520 yen and rival Mitsui & Co <8031.T> shed 4.1 percent to 2,470 yen after U.S. crude oil futures ended sharply lower for the second day in a row on Wednesday.
On the New York Mercantile Exchange, July crude <CLN8> settled down 1.6 percent at $122.30.
Trading houses are considered part of the natural resource sector as they have built up stakes in overseas oil fields and mines.
Oil and gas field developer Inpex Holdings Inc <1605.T> fell 1.6 percent to 1.27 million yen.
Softbank jumped 4.6 percent to 1,951 yen, making it the biggest positive contributor to the Nikkei.
STOCKS DE JOUR?
Fishery-related stocks shot up, with Japan's top seafood firm Maruha Nichiro Holdings Inc <1334.T> jumping 7.1 percent to 211 yen.
Fishery product wholesaler Tohto Suisan Co Ltd <8038.T> soared 14 percent to 245 yen and seafood trade firm Hohsui Corp <1352.T> rose 9.9 percent to 177 yen.
Along with environmental stocks, food shares have become popular recently amid concerns for global food crisis heightened by a United Nations food summit in Rome this week.
"Natural resources, environment and food have become an investment theme, and it has been subdivided into small groups," said Kenichi Hirano, operating officer at Tachibana Securities.
A trading trend has emerged recently, in which a specific set of shares attract retail investors on a given day, and these stocks tend to be small-caps that have been left cheap.
Toyo's Kodama said some retail investors favor these stocks since blue chips that weigh heavy on market indexes are often influenced by index futures trades.
But investors in these stocks are also quick to lock in profit and move on to the next hot sets.
Many battery makers, which soared this week on hopes of a bright future for electric cars, fell on Thursday, with Japan' top car battery maker GS Yuasa Corp <6674.T> down 3.8 percent at 476 yen and Furukawa Battery Co Ltd <6937.T> down 4.2 percent at 841 yen.
Dry cell battery maker FDK Corp <6955.T>, which saw it share price double in the last three days, plunged 8 percent to 253 yen.
Trade picked up, with 1.2 billion shares changing hands compared to last week's morning average of 857 million.
Decliners outnumbered advancers by 814 to 745.