Asian stocks were set to decline after US equities fell, driven by rising oil prices and bond yields. The S&P 500 dropped 0.9%, with Walmart shares plunging the most since 2022 following disappointing sales. The Nasdaq 100 fell 0.7% for a fifth straight session. Equity-index futures signaled declines in Japan, South Korea, and Australia, while US contracts remained largely unchanged. Brent crude surged as much as 3.4% to nearly $95 a barrel, its highest in almost four weeks, after President Donald Trump threatened Iran with "economic warfare." The dollar strengthened, and Bitcoin topped $72,000.

Thirty-year US bond yields rose despite Treasury Secretary Scott Bessent flagging potential for larger debt buybacks and an upcoming fiscal plan. The 10-year yield ended six basis points higher at 4.70%, extending a volatile period for bonds. Traders initially welcomed the Treasury's announcement to increase buybacks of longer-dated debt, but enthusiasm faded quickly. "It was just a housekeeping move destined to be short-term, at best," said Mark Malek, chief investment officer of Muriel Siebert & Co.

Bessent downplayed market moves, calling 24-hour fluctuations "noise," and suggested expanded buyback operations could exceed the planned $4 billion. However, Hardika Singh at Fundstrat Global Advisors noted that bringing down multi-decade high yields would require addressing underlying debt concerns. Investors now await Federal Reserve Chairman Kevin Warsh's speech at the Jackson Hole Economic Policy Symposium for guidance on interest rate policy.

In corporate news, Alibaba Group reported a profit decline of over 75% as it increased quarterly capital spending to nearly $10 billion to compete in the global AI market. Meanwhile, Anthropic PBC is reportedly planning an IPO that could match or exceed SpaceX's record offering, according to sources familiar with the matter.