By EDITH M. LEDERER
UNITED NATIONS (AP) — The United States and its allies have clashed with Iran and its ally Russia over Western claims that Tehran is supplying Moscow with drones that have been attacking Ukraine. And the U.S. accused the U.N. secretary-general of “yielding to Russian threats” and failing to launch an investigation. At a contentious Security Council meeting Monday on the resolution endorsing the 2015 nuclear deal between Iran and six major powers, the United States and Iran also accused each other of responsibility for stalled negotiations on the Biden administration rejoining the agreement that former President Donald Trump pulled out of in 2018. Iran’s U.N. ambassador said the ball is in the U.S. court. The U.S. deputy ambassador said the ball is in Iran’s court.