Asian shares traded mixed on Friday, mirroring a downturn on Wall Street, as a U.S. Treasury Department initiative to increase its government debt buybacks provided only a limited buffer against market volatility. U.S. futures showed a slight uptick.

Japan's Nikkei 225 index shed 0.2%, South Korea's Kospi rose 0.9%, and Hong Kong's Hang Seng gained 0.7%. The Shanghai Composite remained unchanged. Australia's S&P/ASX 200 was down 0.3%, Taiwan's Taiex added 0.4%, and India's Sensex edged 0.1% lower.

The Treasury Department announced Wednesday a plan to at least double the size of its planned purchases of longer-term government debt. Treasury Secretary Scott Bessent further indicated Thursday that the repurchase program could be expanded.

This announcement had a temporary effect on easing government bond yields, which have been elevated due to concerns over high inflation, partly attributed to the war in Iran, and increasing U.S. government debt. Higher yields typically dampen economic activity by increasing borrowing costs throughout the financial system and can depress stock prices.

However, analysts suggest the impact on bond yields is likely to be transient. The yield on the U.S. 10-year Treasury was trading around 4.71% early Friday, an increase from approximately 4.64% on Thursday and returning to levels seen before the Treasury's announcement. The 30-year Treasury yield stood at about 5.26%, up from 5.18% the previous day.

Bond yields in Asia also saw an increase. Japan's 10-year government bond yield, which had been near 30-year highs, rose to 2.88% from about 2.83% on Thursday.

The recent rise in bond yields has exerted downward pressure on stock prices. On Thursday, the S&P 500 lost 0.9%, the Dow Jones Industrial Average fell 1.3%, and the Nasdaq composite dropped 1%.

In other market movements Friday, oil prices experienced a slight decline. This occurred even as the U.S. intensified economic pressure on Iran amidst limited progress in de-escalating tensions between Washington and Tehran. Brent crude, the international benchmark, fell 0.2% to $93.64 a barrel, compared to roughly $72 per barrel before the conflict began. U.S. crude benchmark prices were down 0.3% to $86.59 a barrel.

The U.S. dollar weakened to 159.01 Japanese yen from 159.05 yen. The euro traded at $1.1694, up from $1.1678.