China lifted tariffs of as much as 23 percent that it imposed on some types of hot and cold-rolled steel, stainless steel and other steel products November last year.
"China has greatly contributed to gains this year among some of the raw material stocks and that's going to continue into next year," said Kikuo Osone, who helps manage US$7.1 billion at Fukoku Capital Management Inc in Tokyo.
Increasing demand from Asia has also raised optimism that shippers will benefit from increased trade within the region.
Nippon Yusen, Mitsui OSK Lines Ltd and Kawasaki Kisen Kaisha Ltd, Japan's three biggest shipping lines, are expected to jointly invest more than ?1 trillion in the next four to five years, the Nihon Keizai Shimbun earlier this week.
Nippon Yusen, Japan's largest shipper, jumped 12 percent this week. The company said it will order four container vessels and invest ?770 billion to build 160 ships over five years as it forecasts marine cargo demand will increase worldwide.
Korea's Kospi Index shed 2.8 percent for the week. SK Corp led declines as speculation diminished that the nation's biggest oil refiner would be taken over by Sovereign Asset Management Ltd and its allies. Its shares dropped 13 percent for the week.
Itochu Corp and Taiyo Oil Co bought a combined 0.74 percent stake in SK Corp for US$24.4 million. The purchase by the two Japanese companies, customers of SK Corp, is meant to help fend off a possible hostile takeover bid by Sovereign, the Seoul Economic Daily said.
Earlier this week, a Seoul court backed SK Corp's plan to sell 10.4 percent of its shares to friendly parties. The stake cannot be used to vote as long as it is held by SK Corp.
Monaco-based hedge fund Sovereign, which has 15 percent of SK Corp, is seeking to oust the SK Corp board at a shareholder meeting in March as it tries to gain control of the company. SK Group earlier asked local creditors of its affiliates and other allies to buy SK Corp shares to win a vote in the March meeting.
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