Rex Tillerson
Rex TillersonReuters

U.S. Secretary of State Rex Tillerson will "very shortly" make an announcement on Iran's nuclear agreement with world powers, White House spokesman Sean Spicer said on Monday, according to Reuters.

Under U.S. law, the State Department must notify Congress every 90 days of Iran's compliance with the 2015 deal. Monday is the deadline, and a senior U.S. official said last week the administration was very likely to say Iran was adhering to the agreement.

"The secretary of state will have an announcement very shortly on that deal," Spicer told reporters, according to Reuters.

"I think you all know that the president has made very clear that he thought this was a bad deal, a bad deal for the United States."

The 2015 deal struck with Iran by the United States, France, Britain, Russia, China and Germany is aimed at preventing Tehran from developing a nuclear weapon by imposing time-limited restrictions and strict international monitoring on its nuclear program.

In return, Tehran received relief from some of the international economic sanctions that were imposed on it.

During the presidential election campaign, President Donald Trump was highly critical of the Iran nuclear deal, saying it was “disastrous” and pledging to annul it.

After he was sworn in as president, Trump described the nuclear deal as “the worst deal I’ve ever seen negotiated” and accused the Islamic Republic of “disrespecting” the United States because of the deal.

Despite this, however, the State Department in May renewed its waiver on the nuclear-related sanctions against Iran that it had suspended as part of the nuclear deal.

While lifting nuclear-linked sanctions, the United States maintains sanctions related to Iran's ballistic missile program, human rights record and its support for international terrorism.