The Iran Project - Mohammad Eslami, the head of Iran's Atomic Energy Organization, has criticized Western countries for increasing political pressure on Iran, stating that such actions will not go unanswered.

Eslami made the comments during a meeting on Monday with the Director General of the International Atomic Energy Agency (IAEA), Rafael Mariano Grossi, in Vienna.

Slamming the biased approach taken to Iran by Western countries, the Iranian nuclear chief said, "By resorting to sanctions ... these countries are trying to use the IAEA's mechanisms to mount pressure on Iran."

The Iranian official noted, "Brutal political pressures exerted by Western countries on Iran will not bear fruit and the Islamic Republic will not allow any politically-motivated pressure to go unanswered."

Eslami urged Grossi to keep the IAEA impartial and professional, and not allow Western states to use the agency's reports as an excuse to pressure Iran.

Tensions between Iran and the IAEA have been rising following Iran's decision to bar certain inspectors from the country.

The IAEA chief condemned this move, claiming it affects the agency's verification activities.

In response, Iranian officials accused the US and European parties to the 2015 nuclear agreement of abusing the IAEA for their political objectives.

Grossi asserted that the IAEA is willing to engage and make progress in providing credible assurances that Iran's nuclear program is peaceful, as agreed upon in a joint statement signed in March.