(LEAD) Seoul shares open lower as U.S. bond yields climb again

Seoul shares opened lower on Friday as U.S. bond yields climbed once more, following overnight losses on Wall Street. The Korea Composite Stock Price Index (KOSPI) fell 0.31 percent to 6,831.53 by 9:15 a.m. local time. Earlier, U.S. Treasury yields had resumed their upward trend after the U.S. Treasury announced an expanded bond buyback plan.

However, investors grew skeptical that the buybacks would provide long-term relief from rising borrowing costs. U.S. stock markets suffered overall, with the Dow Jones Industrial Average dropping 1.32 percent and the S&P 500 falling 0.87 percent. The tech-focused Nasdaq Composite Index declined 1 percent. Higher oil prices, including a 2 percent rise in Brent crude, further weighed on stocks amid renewed tensions between the U.S. and Iran.

Most shares in Seoul traded lower, although chipmakers like Samsung Electronics and SK hynix managed modest gains. Battery manufacturer LG Energy Solution fell 2.65 percent, while Hyundai Motor declined 1.2 percent. The Korean won strengthened to 1,391.4 per U.S. dollar, up from the previous session's close.