Iran vows to retaliate after US widens sanctions

By Yasmine Ghania and David Lawder CAIRO/WASHINGTON, Aug 25 (Reuters) - Iran promised to retaliate against expanded U.S. economic sanctions that the Americans said would cut off Iran's economic lifeline, with Tehran expressing confidence that major trading partners would resist Washington's pressure campaign. U.S. Treasury Secretary Scott Bessent unveiled the measures on Monday but stopped short of the most punishing sanctions, saying countries that continued trading with Iran risked being…