"We hope the governors' council of the International Atomic Energy Agency (IAEA) in Vienna does not give in to pressure and that political issues do not interfere with our cooperation with the agency," Kharazi said in Sofia after talks with Solomon Passi, his Bulgarian counterpart.
The Iranian minister's remarks came hours after the United States accused Iran of being in breach of nuclear safeguards agreements but supported a last chance for Tehran to clear up questions about its atomic program by October 31, at a meeting by the UN nuclear watchdog.
Over the past few months the United States, the European Union, Russia and other countries have been pressing Iran to sign an additional protocol to the nuclear non-proliferation treaty to pave the way for in-depth inspection of the country's nuclear facilities.
Both the United States and France suspect Iran of developing atomic weapons under cover of a civil nuclear program.
"Our intention is to continue the negotiations and sign the additional protocol," said Kharazi.
Kharazi claimed Iran "had in practice met the terms of the additional protocol" as it had given "inspection teams access to facilities they had not seen before" and they had "taken samples" in the relevant areas.
"We do not accept the declaration from certain countries that signing on to the protocol would not be enough," Kharazi added.
He stressed that Iran was willing to co-operate with the IAEA to enable the agency to take decisions based on facts.
Bulgaria is a member of the 35-state IAEA board of governors, as well as a non-permanent member of the UN Security Council.
The IAEA governors have the power to refer the matter to the UN Security Council, which could in turn impose sanctions on Tehran.
Kharazi is on a two-day visit to Bulgaria to discuss the international situation regarding Iran as well as bilateral issues in meetings with his counterpart Solomon Passy, President Georgy Parvanov and Prime Minister Simeon Saxe-Coburg, the Bulgarian foreign ministry said.