Asian shares gain, with South Korea’s Kospi up 6%, after the US Treasury expands its debt buybacks

Asian stock markets experienced an upward trend on Thursday, mirroring gains on Wall Street, with South Korea's key Kospi index surging over 6%. U.S. futures also edged higher after the U.S. Treasury Department revealed plans to double the size of its existing purchases of longer-term government debt, potentially easing pressure on stocks from the bond market. Consequently, bond yields fell, providing relief to investors concerned about rising interest rates.

South Korea's Kospi index rose 6.1% to 6,858.91, after closing 5.8% lower on Wednesday due to renewed concerns about artificial intelligence-related stocks. Samsung Electronics and memory chipmaker SK Hynix led the gains in South Korean markets, with the former rising 9.7% and the latter surging 14.1% following Samsung's announcement of a substantial share buyback plan.

Japan's Nikkei 225 index climbed 1.3% to 66,178.26, reversing earlier week's declines, while the Japanese government reported a trade deficit for the third consecutive month in July, as both imports and exports reached record highs. Shares of SoftBank Group, a prominent Japanese investment firm, jumped 3.8%.

Hong Kong's Hang Seng index gained 1.1% to 25,786.32, while the Shanghai Composite index increased by 0.3% to 3,905.23. Although Australia's S&P/ASX 200 and Taiwan's Taiex saw minimal gains, India's Sensex rose 0.7%.

U.S. government bond yields declined following the Treasury Department's announcement of expanded debt buybacks, as falling yields typically accompany rising bond prices. The move seemed to calm investors' fears about increasing interest rates. Earlier in the week, the S&P 500 and Dow Jones Industrial Average both climbed by 0.2%, while the Nasdaq composite also rose 0.2%.