The head of the International Atomic Energy Agency (IAEA) Rafael Grossi will land in Tehran late Friday for talks on the Islamic Republic's nuclear activities, Iran's state media outlets reported. The visit comes as nuclear talks hit a stalemate with the West, and amid warnings that Iran's uranium enrichment is closer to the weapons-grade bar. 

On his fourth trip to Tehran since taking the helm in late 2019, Grossi is expected to sit down with Iran's atomic chief Mohammad Eslami. More importantly, however, he is reported to have requested a meeting with hard-line President Ebrahim Raisi.

Despite a period of relatively stable cooperation between the two sides after the implementation of the 2015 Iran nuclear deal, relations between Tehran and the IAEA have increasingly strained over the past two years. The watchdog accuses Tehran of stonewalling probes into its nuclear enrichment program, most notably after inspectors detected activity at two undeclared sites last year.

Under the nuclear deal, the Joint Comprehensive Plan of Action (JCPOA), Iran was required to adhere to a strict cap of 3.67% on its enrichment in exchange for sanctions relief. Nonetheless, since the US withdrawal from the accord in 2018, the rate has been exponentially raised as high as 60%. In justifying the breaches, Iran has also cited the three European signatories' failure to deliver on the JCPOA's promised economic dividends.