Seoul stocks fell Tuesday as rising U.S. Treasury yields and oil prices weighed on investor sentiment, with the benchmark KOSPI opening lower and remaining in negative territory for most of the session. The index opened at 6,844.41, down 0.66 percent from the previous close, according to the Korea Exchange. It moved in a narrow range below the flat line before closing at 6,870.81, down 0.27 percent. Retail investors and institutions were net buyers of 1.14 trillion won ($842 million) and 121.1 billion won, respectively, while foreign investors sold a net 2.9 trillion won. Oil prices rose and U.S. Treasury yields remained elevated amid the escalating standoff between Washington and Tehran. Over the weekend, U.S. President Donald Trump rejected an Iranian proposal to reopen the Strait of Hormuz and resume nuclear talks in exchange for the lifting of a U.S. naval blockade, among other concessions. The yield on the 10-year Treasury note, a global benchmark for borrowing costs, remained above 5.2 percent, its highest level since mid-2007. Higher yields and oil prices weighed on Wall Street over