IRNA � President Donald Trump's unnecessary demands on Iran have put at risk the United States reputation in the International Atomic Energy Agency, a former White House expert said, as the UN nuclear watchdog remains to confirm Tehran's commitment to the nuclear deal.

'Important story. US pressure or not, UN nuclear watchdog sees no need to check Iran military sites,' Richard Nephew the former sanction expert of white house wrote recently on his twitter page.

Iran and the world major powers in 2015 signed a historic nuclear deal, known as the Joint Comprehensive Plan of Action (JCPOA) to end the impasse over Iran's peaceful nuclear activities.

'A really sad aspect of this whole debacle in waiting is that the United States has spent the best part of 15 years repairing its rep with the IAEA and others when it comes to issues like nuclear intelligence,' he added.

Pointing to his decade-long efforts in the US negotiating team with Iran, the senior research scholar at the Center on Global Energy Policy at Columbia University went on to say that, 'this was not an easy thing to do. Restoring credibility and trust on these matters took time, consistent accuracy and humility.'

'To see it all go to hell and for no good reason is upsetting,' Nephew added.

He also warned that in future cases when credibility is needed, the US would be disappointed.

The IAEA published last Thursday its eighth report and the third since Trump has taken office in January 2017, to confirm that Iran has been committed to the deal.

The report comes a week after the visit of the US representative in the UN Nikki Haley to IAEA in Vienna to press the United Nations nuclear watchdog to seek access to Iran's military sites.

According to some US media reports, Trump and his team are trying to put together some documents to show that Iran is not complying with the agreement.

However, following the visit by Haley to IAEA, Western media reported that the Trump administration has no evidence that indicates there has been some suspicious activity in Iranian military bases.

'Haley is not reported to have presented any new evidence about suspicious activity at any Iranian site, nor named any military base she believes should be investigated,' according to the Guardian.

Nephew's warning is not the only on President Trump's approach towards the deal.

Experts have already warned on the consequences of the administration's attempts to lobby the international bodies to reject Iran's commitment.

Politicizing the 'international open source information' by Washington would undermine the utility of such reports, the former CIA official David Cohen had recently warned, referring to Trump's attempts to kill Iran nuclear deal.