Top UN nuclear inspector: Iran deal must not fail

The head of the UN nuclear agency says a deal between Iran and six other nations aimed at ensuring Tehran doesn't develop atomic weapons mustn't fail.

President Donald Trump has repeatedly threatened to withdraw the United States from the landmark 2015 agreement, and last year refused to confirm to Congress that it is in America's national security interest.

The head of the Vienna-based International Atomic Energy Agency said on Monday that "Iran is implementing its nuclear related commitments" and that "it is essential that Iran continues to do so."

Yukiya Amano said that if the deal "were to fail it would be a great loss for nuclear verification and multilateralism."

Amano said UN inspectors had access to all required sites and between them now spend 3,000 calendar days a year working in Iran.