The talks in Austria's capital are aimed at bringing the United States back into the world powers' 2015 deal with Tehran on its nuclear programme.
The talks in Austria's capital are aimed at bringing the United States back into the world powers' 2015 deal with Tehran on its nuclear programme.
United States says Iranian IRGC vessels came close to US Navy and Coast Guard ships on Monday evening.
Tehran and other world powers met in Vienna on Tuesday, with the US participating indirectly.