Asian stocks wobble over sovereign debt fears

Global bond yields have hovered near their highest for decades as fears over swelling sovereign debt pushed borrowing costs higher and rattled stock markets worldwide.

The yield on the US long bond hit its highest in nearly 20 years on Tuesday, at 5.3371 per cent, before steadying around 5.28 per cent in Asia on Wednesday. The 10-year and 30-year bund yields hit their highest since 2011.

The French 30-year yield is up nearly 50 basis points since the end of June and Japan's once-zero 10-year yield is closing in on three per cent as inflation rises and investors fret policymakers are moving too slowly to counter it.

"Investors are no longer taking on faith that (government) spending gets brought under control. Indeed, they're pricing the risk that it doesn't," said Nigel Green, CEO of financial advisory deVere Group.

Bond selling eased in steady Asian morning trade, but the inflation outlook remained troubling with Brent crude futures parked above $US90 a barrel on no signs of progress toward a deal to open the Strait of Hormuz to oil tankers.

Later on Wednesday the US Federal Reserve releases minutes from the July meeting where it left rates on hold, but Chair Kevin Warsh spooked markets by offering few clues about whether and how the central bank might respond to persistent inflation.

MSCI's broadest index of Asia-Pacific shares outside Japan fell 1.7 per cent. South Korea's KOSPI led the retreat, dropping 5.2 per cent and Japan's Nikkei was down 2.6 per cent, following tech-led losses on Wall Street overnight.

In China, shares in the world's biggest humanoid-robot maker, Unitree, soared 600 per cent on debut, a listing that was more than 8000 times oversubscribed by retail investors.

Asia's broader technology and semiconductor stocks came under pressure, tracking overnight losses on Wall Street and from reports that Anthropic's annual revenue run-rate topped $US65 billion at the end of July, which was behind some market hopes.

The risk-averse mood has lent a little support to the dollar in currency markets, though moves were small.

The Canadian dollar rose a tad after US President Donald Trump paused imposing a 50 per cent tariff on Canadian goods for three days, saying the countries had reached a deal.

The euro hovered at $US1.1576 and the yen traded at 159.44 per dollar, just in the shadow of 160 - a level investors see as a potential trigger for another round of official intervention.

British inflation data on Wednesday is due along with earnings at Lowe's, Target and TJX which will be closely watched after softer-than-expected US retail sales data landed last week.

Home Depot beat estimates for second-quarter sales and profit on Tuesday, on strong demand from customers for repair and maintenance, though US data showed homebuilding dived in July, hit hard by rising mortgage rates.