President Mahmoud Ahmadinejad insisted today that Iran would resume atomic research despite warnings from the West that this would endanger efforts to find a diplomatic compromise.
Tuesday's announcement of a resumption after a break of more than two years brought swift warnings from Washington and the European Union who fear Iran is building nuclear weapons.
"Some of them have said the Iranian nation has no right to nuclear research," Mr Ahmadinejad said in a speech in the holy city of Qom broadcast on state television.
"But they should know that the Iranian nation and government will defend the right to nuclear research and technology and will go forward prudently."
Western diplomats have said the move, which followed its resumption of uranium conversion in August, was likely to increase calls for Iran to be referred to the UN Security Council for possible sanctions.
Enriched uranium can be used to make nuclear weapons, although Iran says it only wants to produce low-grade enriched uranium to make electricity in atomic power reactors.
France said Iran's planned resumption of research from January 9th undermined negotiations with Iran by the EU trio of Britain, Germany and France.
"We firmly call for Iran to back down from the announcement that it intends to restart certain research and development activities, a foreign ministry spokesman said.