US-Iran Tensions Weigh on Asian Stocks as Oil Prices Hold Steady

Asian stock markets were mostly lower on Tuesday following a mixed finish for US stocks ahead of potentially market-moving events. The regional benchmarks traded in a narrow range, with U.S. futures nearly unchanged. Oil prices remained steady after the US Treasury Secretary announced fresh sanctions against Iran and warned countries doing business with the Islamic Republic would face retaliation.

The Nikkei 225 in Tokyo gained 0.4% to 65,811.19, while the Kospi in South Korea fell 0.4% to 6,675.88. Hong Kong's Hang Seng lost 0.3% to 25,453.19 and the Shanghai Composite index edged 0.1% lower, to 3,878.38.

The S&P/ASX 200 in Australia gained 0.6% to 9,158.70. Taiwan's Taiex edged less than 0.1% lower, while the Sensex in India lost 0.3%. The US Treasury Department's surprise move to increase the size of its planned buybacks of Treasurys may have eased pressure on stocks.

However, analysts say the buybacks are relatively small and will not address fundamental problems such as excessive government debt and high oil prices due to the war with Iran. Long-term Treasury yields climbed this summer on worries about inflation, huge government debts, and other factors.