China stocks light up
China's Shanghai Composite index powered up in the final hour of trading to finish 4.9 percent higher, shaking off lackluster momentum from earlier in the day which saw the index fluctuate between modest gains and losses.
According to Reuters, the late-day swing marked the bourse's best one-day gain since August 27, with over 1,000 stocks closing up by the daily maximum allowable of 10 percent.
The CSI300 Index — which tracks the largest listed companies in Shanghai and Shenzhen — rocketed 5 percent, with majority of the gains attained in the final 15 minutes before the market close at 3pm local time. Among the small-cap indexes, the Shenzhen Composite and and the start-up board ChiNext widened gains to more than 6 percent each, recovering from the steep selloff in previous sessions.
Analysts who spoke to CNBC said the late-day swing followed the familiar pattern in mainland markets which is typically likened to government intervention.
"While there is no specific evidence, it follows the pattern involving state-backed buying which sees the markets surging around 1 or 2pm local time," Daniel So, strategist at CMB International Securities, told CNBC by phone.
IG market strategist Bernard Aw agreed: "It is quite likely and quite suspicious that it is state buying [because] it cant be that investors decided to start buying in the last hour."
Aw added that authorities have begun "staggering their buying so as not to create a moral hazard."
"They don't do it everyday now. The China Securities Regulatory Commission (CSRC) came in almost everyday in July, but I guess they are starting to realize that investors may be trying to game the system so they started to stagger. Other reasons may be that it is getting too costly to support the market," Aw told CNBC by phone.
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Among gainers, property heavyweights such as Poly Real Estate and China Vanke closed up 4.9 and 3.2 percent respectively, while brokerage houses such as Haitong Securities shot up 8.4 percent, unaffected by local media reports that the president and two other executives of Citic Securities are under police investigation for suspected insider trading and leaking information.
The Hong Kong-listed shares of Citic closed down 0.7 percent in choppy trade, while its A-shares rose 7 percent. Following the news reports, Jefferies cut its price target for the stock to HK$26.50 with a 'buy' rating.
"[The stock reaction] is strange because fundamentally it is not a good news. We don't know whether there would be more brokers involved in investigations later, just like Citic Securities, so [this uncertainty] won't be good for securities stocks," CMB International Securities' So said.
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Nikkei gains 0.8%
Japan's benchmark Nikkei 225 index followed its U.S. counterparts higher on Wednesday.
Export-oriented stocks attracted hefty buy orders; Honda led advances in the sector, up 3.5 percent, while Toyota Motor, Nissan and Suzuki Motor elevated between 1.6 and 2.7 percent. Panasonic and Sony rose 3.4 and 1.2 percent respectively.
Banking stocks also gained ground; Mitsubishi UFJ Financial Group and Sumitomo Mitsui Financial Group closed up over 1 percent each.
Orix Corp climbed 2.5 percent on the back of a report by the Nikkei business daily that it is acquiring an 85 percent stake in Sinar Mitra Sepadan Finance.
ASX up 1.6%
Broad-based gains across all key sectors helped Australia's key S&P ASX 200 index to recover from Tuesday's one-week closing low.
According to a note by Patersons Securities, expectations for a delay in the Fed's policy tightening timeline lifted risk appetite. "After the U.S. markets lifted 1.28 percent last night on expectations that the FOMC will not lift rates in September, the U.S. futures market has lowered the probability of an U.S. interest rate hike in September to 28 percent, and for good reason," analysts wrote.
"A quick glance at the global and U.S. numbers suggests an interest rate lift is not necessary and quite risky," Patersons Securities added.
All four major lenders closed up over 2 percent each, while market bellwether BHP Billiton made gains of 2.3 percent, mirroring the 2.1 percent jump in the miner's U.S. ADRs overnight. Rivals Rio Tinto and Fortescue Metals surged 1.1 and 2 percent respectively.
Woodside Petroleum moved up 3 percent following a report by the Sydney Morning Herald that its chief executive Peter Coleman will hold talks with the Papua New Guinea government to consider whether to sweeten a $11.6 billion takeover bid that was rejected by Oil Search earlier this week. Shares of the latter widened gains to 2.2 percent.
Meanwhile, media companies rallied for a second straight day on hopes of media deregulation under new Prime Minister Malcolm Turnbull. Ten Network, Nine Entertainment and Seven West Media rose nearly 3 percent each.