Asia stocks mixed ahead of Fed, ECB decisions

Asian stocks were mixed on Wednesday ahead of monetary policy decisions in the U.S. and Europe, while worries over Greece also hurt sentiment.

Global investors are awaiting the outcome of the Federal Open Market Committee's two-day meeting as well as the European Central Bank's policy review later in the day. The Fed isn't expected to take any action on interest rates, with consensus for a rate hike pushed to September.
The ECB, meanwhile, could announce a change to Emergency Liquidity Assistance to Greece. Talks between the bankrupt country and its international creditors remain stuck in deadlock as Athens faces a $1.8 billion repayment to the International Monetary Fund by the end of June.

Caution ahead of those two policy decisions overshadowed a positive handover from Wall Street overnight, where the Dow Jones Industrial Average gained more than 100 points, recovering from two days of declines.
ASX 1.1% higher
Australia's S&P ASX 200 index shot up after Warren Buffett told the Australian Financial Review that he will continue investing in Australia following Berkshire Hathaway's stake in insurer IAG this week.

Banks led the rally, with the 'Big Four' lenders, Australia New Zealand Banking , Westpac, National Australia Bank and Commonwealth Bank of Australia, all rallying nearly 2 percent each.

Supermarket firm Woolworths popped 2 percent following the retirement of Chief Executive Grant O'Brien.

China shares mixed

Mainland stocks tanked over 1 percent, extending losses following Tuesday's 3 percent selloff, as investors continued to worry about an upcoming wave of IPOs and margin financing curbs.

"A-shares have some bottom-up concerns. Valuations are exorbitant. Trade velocity is at record highs. Finally, it has the world's highest level of margining and fundamentals are at breakneck levels," said Evan Lucas, market strategist at IG, said in an emailed note Wednesday morning.

In Hong Kong, the Hang Seng Index was flat ahead of a key vote on a controversial China-backed electoral reform package. Several experts say the government should veto the proposal, which allows residents the right to vote for a chief executive in 2017, but maintains that candidates would be chosen by Beijing.
Nikkei dips 0.3%
Japan's benchmark Nikkei index reversed early gains after breaching the 20,300 level in early trade. Trade data for May released before the market open worried investors, with exports missing expectations and imports coming in worse than expected. The index still remains well off a fifteen-year high of 20,655 points hit at the end of May.

Toyota Motor was flat after announcing an additional recall of 1.3 million vehicles on Monday due to faulty Takata air bags.
SoftBank lost 1 percent following news it is setting up a robotics focused joint-venture with Taiwan's Foxconn Technology.

Kospi down 0.2%

South Korea's benchmark Kospi index extended losses after closing at an eleven-week low in the previous session. Investors seemed to ignore news that regulators will develop measures for the market to be included in MSCI's developed markets index .

Large-cap stocks weighed down the index, with Hyundai Motor and Samsung Electronics down half a percent each.