Stocks on Wall Street bounced back on reports of progress toward Greece's debt restructuring and consideration of further measures to aid the US economy.
Greece's debt swap is continuing to secure more support, while a report in the Wall Street Journal says Federal Reserve officials are weighing a new form of stimulus – a long-dated bond-buying programme designed to alleviate near-term inflation fears.
The Dow Jones Industrial Average was up 78.26 points, or 0.6%, to 12,837.34 at the close (10am NZ time). The S&P 500 was up 0.7% at 1352.63 and the Nasdaq Composite was up 0.9% at 2935.69.
Eight of the S&P's 10 sectors are higher, led by financial and industrial shares. Bank of America led blue chips higher, rising 2.3%.
The market's rise is a partial recovery from Tuesday's rout, when the Dow fell more than 200 points in its biggest decline since November. It was the first triple-digit point drop of the year.
Other markets: Europe rebounds, Asia down
European markets moved higher but investors remained cautious ahead of the Thursday deadline for Greece's debt swap.
The Stoxx Europe 600 rebounded 0.6% to 260.11 after shedding 2.7% in the previous session, its biggest fall since November 2011.
The UK's FTSE 100 closed 0.4% higher at 5791.41, Germany's DAX gained 0.6% to 6671.11 and France's CAC-40 closed up 0.9% at 3392.33.
Asian stock markets ended lower, with banks and resource companies among the worst performers, as renewed concerns over global growth and Greek debt dented investor confidence.
Australia's S&P/ASX 200 index dropped 1.5% to 4143.7, Hong Kong's Hang Seng Index lost 0.9% to 20627.78 and Japan's Nikkei Stock Average fell 0.6% to 9576.06.
Korea's Kospi gave up 0.9% to 1982.15, while China's Shanghai Composite fell 0.7% to 2394.79.
Commodities: Oil, gold advance
Crude-oil futures prices followed other markets higher on speculation about potential Fed easing measures and Greek debt moves.
Light, sweet crude for April delivery traded $US1.14 higher at $US105.85 a barrel in New York after trading as low as $US104.35 earlier in the session.
Brent crude on the ICE futures exchange traded 96USc higher at $US122.94 a barrel.
Gold ended higher, snapping a three-day losing streak, as a weaker US dollar gave a boost.
The most actively traded contract, for April delivery, rose $US11.80, or 0.7%, to settle at $US1683.90 an ounce in New York.
Currencies: Euro gains
The euro and Australian dollar firmed after a recent run of losses against the US dollar and yen.
The Australian dollar stabilised above $US1.0550 while the euro was at $US1.3136 compared with $US1.3113 late on Tuesday.