Iran's president Hassan Rouhani said on Sunday that its "rights to enrichment" of uranium were "red lines" that would not be crossed and that the Islamic Republic had acted rationally and tactfully during nuclear negotiations, Iranian media reported.
"We have said to the negotating sides that we will not answer to any threat, sanction, humiliation or discrimination. The Islamic Republic has not and will not bow its head to threats from any authority," he said during a speech at the National Assembly, Iran's student news agency (ISNA) said.
"For us there are red lines that cannot be crossed. National interests are our red lines that include our rights under the framework of international regulations and (uranium) enrichment in Iran," he said.
On Saturday, Iran and six world powers failed in talks to clinch a deal to curb Tehran's nuclear programme but said differences had narrowed and they would resume negotiations in 10 days to try to end the decade-old standoff.
Rouhani, who was elected in June, is the chief architect of Iran's diplomatic drive for a nuclear deal to alleviate harsh economic sanctions on its oil and banking industries.
His negotiating team is pushing to agree a framework for steps to resolve U.S. suspicions that Tehran wants nuclear weapons capability.
The Islamic Republic says its activities are purely peaceful and negotiators say they are ready to take the steps necessary for such an agreement if their nuclear "rights are recognised" and world powers reciprocate by easing sanctions.