Iranian foreign minister says that Tehran remains open to resolving differences over its nuclear program through dialogue and mutual cooperation, as the UN’s nuclear chief held talks in Tehran.

“Important and straightforward talks with DG @rafaelmgrossi this morning,” Araghchi wrote on X, referencing his meeting with IAEA Director General Rafael Grossi on Thursday. “Differences can be resolved through cooperation and dialogue. We agreed to proceed with courage and goodwill.” However, he added that Iran would not negotiate “under pressure and intimidation.”

President Masoud Pezeshkian said on Thursday that Tehran was prepared to cooperate with the UN nuclear watchdog IAEA to clear up "alleged ambiguities about the peaceful nuclear activity of our country", Iranian state media reported.

Grossi’s visit to Tehran, part of a high-level effort to de-escalate nuclear tensions, also included talks with Mohammad Eslami, head of Iran’s Atomic Energy Organization. IAEA's Board of Governors will hold its quarterly meeting next week, where Iran can face a resolution criticizing its lack of cooperation with the UN watchdog.

In a joint press conference, Eslami warned of immediate reciprocal actions should the IAEA Board of Governors issue a resolution targeting Iran's nuclear program.

“We have repeatedly announced that any interventionist resolution regarding Iran’s nuclear affairs will undoubtedly face immediate actions,” Eslami said. “We will not allow pressure to dictate the course of our peaceful nuclear activities.”

Later on Thursday, Tehran media reported that Grossi will visit nuclear facilities in Fordow and Natanz tomorrow. According to these reports, he described this visit as very important, emphasizing that it could provide him with an accurate assessment of the quality and scale of Iran's nuclear program. This marks a shift in his approach, as he did not inspect any facilities during his previous visit to Iran.

Reuters quoted some diplomats on Tuesday that European powers are advocating for a new resolution against Iran at the UN atomic watchdog's board meeting next week to pressure Tehran over its lack of cooperation.

"Our concerns about Iranian nuclear activity are well known. It feels a natural point to be asking the IAEA for a thorough report. That then provides a basis to deal with Iranian behavior," a European diplomat said.

Eslami; however, described Iran’s engagement with the IAEA as continuous and constructive. “These actions tarnish the credibility of international organizations,” he said. “The United Nations and its affiliated bodies must fulfill their responsibilities in addressing these issues.”

Grossi, addressing transparency and oversight concerns, touched upon the importance of IAEA verification, which he said requires a clear framework. He said there must be a comprehensive basis for the activities, including a detailed list of nuclear materials and clarity on capabilities, adding that this applies not only to Iran but to all nations.

On the potential for military attacks on nuclear facilities, Grossi warned of severe consequences. “Such attacks could have very serious radiological consequences,” he said. “The IAEA and its member states have previously expressed strong opposition to such actions.”

Grossi emphasized the need for tangible progress, saying, “It is indispensable to get at this point in time to some concrete, tangible, visible results that will indicate that
this joint work is improving the situation and bringing clarification to things and in a general sense is moving us away from conflict and ultimately war.”

Grossi’s visit follows his earlier warnings that diplomatic avenues to resolve Iran’s nuclear activities are narrowing. Speaking at the COP29 climate summit in Baku, he urged Iran to enhance transparency, saying, “We need to find ways of giving the agency more visibility.”

The visit comes after weeks of tensions in the region, particularly between Iran and Israel. Ahead of his trip, Grossi told AFP, “The Iranian administration must understand that the international situation is becoming increasingly tense and that it is imperative to find ways to reach diplomatic solutions.”

Meanwhile, Israel has expressed alarm over Iran’s nuclear progress, as has the international community. Donald Trump's election has added further uncertainty to the future of the 2015 nuclear deal. Trump’s 2018 withdrawal from the accord unraveled its framework, despite subsequent efforts to revive it. Grossi has described the accord as an “empty shell,” calling for a new framework to address the current challenges.

The 2015 Joint Comprehensive Plan of Action (JCPOA), brokered between Iran and six world powers, sought to limit Iran’s nuclear activities in exchange for sanctions relief. However, in the absence of a binding agreement, Iran’s nuclear program has significantly expanded.

According to the IAEA, Tehran’s enriched uranium stockpile has grown, with enrichment levels reaching 60%—approaching the 90% threshold required for weaponization. While Tehran denies any intention of developing nuclear weapons, the expanded program has fueled international concerns.