The U.N. atomic watchdog chief says his inspectors have yet to encounter problems with Iran a week after U.S. President Donald Trump refused to certify that Tehran was complying with a 2015 nuclear deal.

Trump's stance put him at odds with key U.S. allies, including Britain, France and Germany who helped negotiate the deal

U.S. President Donald Trump announced he is decertifying the Iran nuclear deal - a historic agreement signed under the Obama administration.