Asian stocks fell for a second day on Thursday as lacklustre earnings reports from tech megacap stocks deepened a sell-off on Wall Street, while US sanctions against Russia and China revived fears around geopolitics and pushed oil prices higher.

In Hong Kong, the benchmark Hang Seng Index fell 63 points, or 0.25 percent, to open at 25,718.

On the mainland, the benchmark Shanghai Composite Index opened down 0.25 percent at 3,904, while the Shenzhen Component Index was 0.29 percent lower at 12,959.

The ChiNext Index, tracking China's Nasdaq-style board of growth enterprises, was down 0.28 percent at 3,050.

MSCI's broadest index of Asia-Pacific shares outside Japan was last off 0.3 percent, while Japan's Nikkei 225 sank 1.5 percent.

Chinese stocks declined in Hong Kong following reports that the White House is considering a plan to curb an array of software-powered exports to China to retaliate against Beijing's latest round of rare earth export restrictions.

"With no fresh macro data to anchor sentiment, investors are leaning defensive while US President Donald Trump’s Asia visit stirs geopolitical nerves," said Charu Chanana, chief investment strategist at Saxo Bank in Singapore.

"The chatter around US software export curbs to China has hit tech sentiment right where it hurts, and renewed sanctions on Russia are a reminder that geopolitical risks aren’t going away either."

Global equity markets are easing off record highs as corporate earnings season kicks off. While results or outlooks from the megacaps have disappointed investors, most of the companies that have reported so far have beaten analysts' estimates.

South Korean stocks fell 0.2 percent after the Bank of Korea kept rates on hold, as expected by analysts.

Brent crude was last up 2.3 percent at US$64 per barrel after Trump on Wednesday imposed Ukraine-related sanctions for the first time in his second term, targeting Russian oil companies Lukoil and Rosneft. The move came the same day as EU countries approved a 19th package of sanctions on Moscow that included a ban on Russian liquefied natural gas imports.

S&P 500 e-mini futures edged up 0.1 percent after a second day of declines for US stocks overnight as earnings reports from tech megacaps underwhelmed analysts on Wall Street. (Reuters/Xinhua)