Iran's decision to enrich uranium is irreversible, its foreign ministry said last night.
Iran, accused by Western nations of seeking nuclear bombs, said this month it had enriched uranium for the first time to a level used in power stations.
Western nations have threatened to seek sanctions on Iran if it does not stop enrichment. The United States has not ruled out military action, a step other Western states, as well as Russia and China, oppose.
The International Atomic Energy Agency (IAEA) is due to report by April 28th on whether Iran is complying with a UN demand that it halt enrichment, a process that can have civilian and military uses.
"If the (IAEA) report contains expert assessment, there will be nothing left to worry about," a foreign ministry spokesman said.
"However, if the report comes out and somehow puts pressure on Iran or speaks with a language of threats, naturally Iran will not abandon its rights and it is prepared for all possible situations and has planned for them," he said.
Iran says its nuclear programme is purely for generating electricity. Western nations say the only way for Tehran to prove it is not seeking atomic bombs is to renounce all sensitive nuclear technology.
Top US congressional intelligence committee members said yesterday that Washington did not have enough intelligence to know if Iran was capable of producing nuclear weapons in the near future.