The U.S. and NATO are working on a novel approach to supply Ukraine with weapons using funds from NATO countries to pay for the purchase or transfer of U.S. arms, according to three sources familiar with the matter. The renewed transatlantic cooperation on Ukraine comes as U.S. President Donald Trump has expressed frustration with Moscow's ongoing attacks on its neighbor. Trump, who initially took a more conciliatory tone toward Russia as he tried to end the more than three-year war in Ukraine, has threatened to start imposing tariffs and other measures if Moscow shows no progress toward ending the conflict...