Wall Street moved higher overnight, bolstered by gains in Apple shares after Warren Buffett's Berkshire Hathaway disclosed that it owns a stake worth about US$1.1 billion in the iPhone maker. Oil also helped underpin the mood.
In 2.53pm New York trading, the Dow Jones Industrial Average rallied 1.1 percent, while the Nasdaq Composite Index climbed 1.5 percent. In 2.38pm trading, the Standard & Poor's 500 Index gained 1.1 percent.
Gains in shares of Apple and those of Home Depot, recently trading 4 percent and 2.3 percent stronger respectively, led the Dow higher.
Berkshire held 9.81 million Apple shares as of March 31, according to a regulatory filing.
Apple stock "is stunningly cheap, and it has a massive pile of cash," Steve Wallman, founder of Wallman Investment Counsel in Middleton, Wisconsin, who has owned Berkshire since 1982 and Apple since 2003, told Reuters. "Apple is not getting credit for research and development it is doing behind the scenes."
Equities also received a lift from oil, which advanced more than 2 percent. Goldman Sachs became more upbeat about the outlook, predicting US crude might rise as high a US$50 a barrel in the second half of this year.