Nikki Haley, the US ambassador to the UN, on Tuesday told the world's atomic watchdog that the White House has "concerns" about Iran's adherence with the 2015 nuclear deal.

During discussions with International Atomic Energy Agency (IAEA) chief Yukiya Amanao, Haley asked whether the atomic agency is prepared to visit Iranian military sites to ensure compliance.

Read more: Opinion: Iran's risky nuclear deal threat

"If you look … at past Iranian behavior, what you've seen is there have been covert actions at military sites, at universities, things like that," Haley told Reuters news agency.

"There were already issues in those locations, so are they including that in what they look at to make sure that those issues no longer remain? … They have the authority to look at any suspicious sites now. It's just are they doing it?"

Under the administration of US President Donald Trump, Washington has increasingly criticized Iran. Even before assuming office, Trump has lashed out at the nuclear deal, describing it as the "worst deal ever negotiated."

'Renegotiate'

Sascha Lohmann of the Berlin-based German Institute for International and Security Affairs (SWP) told DW earlier this month that both Trump and Congress are skeptical about the deal.

"A broad majority is in favor of scrapping the deal or trying to renegotiate a better one. That means there is a great danger that things may soon chance on the US end of the agreement in the very near future,” Lohmann said.

Years in the making, the nuclear deal of 2015 marked a major diplomatic victory for Germany, China, France, Russia, the UK and the US, which sought to limit Tehran's ability to develop a nuclear weapon.

Despite US concerns, the IAEA in June reported that Iran has continued to follow rules set out in the deal that curbed its nuclear program in exchange for the international community lifting sanctions against the Islamic Republic.

ls/ (AFP, Reuters)