ASX rises 0.6%
Australia's S&P ASX 200 index finished higher, propped up by the steep gains in the oil and gas sector on the back of firmer oil prices overnight. Oil Search climbed 5.7 percent, while Santos and Woodside Petroleum rose 4.4 and 2 percent each.
Junior miners remain in focus after Atlas Iron sought a trading halt on Tuesday. "The news from Atlas Iron was something I have long suggested was coming and I don't believe it will be the last bad news on the wires. I have concerns for BC Iron, Mount Gibson and the junior play Gindalbie Metals," Evan Lucas, IG's market strategist, wrote in a note.
Shares of BC Iron and Gindalbie Metals tanked nearly 10 percent each, while Mount Gibson erased gains to close virtually unchanged.
Banks, however, failed to overcome the disappointment from the Reserve Bank of Australia's (RBA) decision to hold borrowing costs steady at a record low of 2.25 percent yesterday. Commonwealth Bank of Australia and Australia and New Zealand Banking slipped 0.3 and 0.2 percent each.
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Kospi adds 0.6%
South Korea's Kospi index closed up at a more than 5-month high, thanks to a steady upswing among the country's oil refiners. S-Oil and SK Innovation rose 8.9 and 7.8 percent, respectively.
Hyundai Steel and Hyundai Hysco rallied 6 and 8.2 percent each on news of a merger. Meanwhile, the bourse's top weighted stock Samsung Electronics, which released its guidance on first-quarter results Tuesday, gained 0.8 percent.
Rest of Asia mixed
India's Nifty index gained 0.6 percent, recouping losses in the previous session sparked by the Reserve Bank of India's (RBI) decision to leave its main repo rate at 7.5 percent.
In Singapore, shares of Singapore Telecommunications threw away gains to retreat back to neutral territory following news that the telecom service provider will be acquiring Trustwave Holdings, a privately-held information security company based in Chicago. The broader Straits Times index dipped 0.1 percent.
Taiwanese manufacturer of smartphones and tablets HTC dropped 2.5 percent despite announcing better-than-expected first-quarter profit, outpacing a 0.7 percent drop in the broader Taiex index.