Last month, Tehran announced it would allow the International Atomic Energy Agency (IAEA) to two sites following a visit to Iran by director general Rafael Grossi. The exact locations have not been revealed.
In a statement, the IAEA said: “As part of an agreement with Iran to resolve safeguards implementation issues specified by the IAEA, the agency this week conducted a complementary access at the second location in the country and took environmental samples.”
Iran agreed to allow the IAEA access to both sites on specific dates later this month.
Earlier this year, Tehran denied the agency access to the locations which prompted IAEA’s board of governors to pass a resolution urging Iran to comply with its requests.
In March, the IAEA identified two sites as places where Iran could have stored or used undeclared nuclear material or undertaken nuclear-related activities without declaring them.
One site was reported to be in Abadeh, south of Isfahan.
This location was flagged by Prime Minister Benjamin Netanyahu as the site of an alleged secret nuclear facility in 2019.
Back in July, it was claimed there are multiple underground cities armed with long-range missiles throughout Iran.
Iran’s Revolutionary Guard Navy commander Rear Admiral Alireza Tangsiri said the weapons were a “nightmare” for Iran’s foes.
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“Statements like this demonstrate clearly that the Islamic Revolutionary Guard Corps and its leaders are a destabilising force in the region.”
Over recent years, Iran has shown off a series of underground tunnels and command centres across the country.
These tunnels are home to the largest and most advanced missile program in the Middle East.
Despite some analysts trying to pinpoint the facilities, Admiral Tangsiri said Iran’s foes had “inaccurate information”.
Tensions between the US and Iran have intensified over recent months.
The two countries were on the brink of war back in January after US forces killed Iranian major general Qassem Soleimani during a missile strike in Iraq.
General Soleimani was travelling through Baghdad when his convoy was struck by three US missiles.
Just days after the attack, Tehran retaliated and launched a series of ballistic missiles at two Iraqi bases housing US troops.
Washington has been seeking an extension of a United Nations (UN) arms embargo against Tehran, under the Trump administration.
This is set to expire in October under the 2015 Iran nuclear deal which the US withdrew from.
The nuclear deal had restricted Iran’s nuclear weapons capability in return for sanctions relief.
However, Mr Trump abandoned the agreement in 2018 and has gone on to introduce a number of sanctions on Iranian oil exports.