The United Nations security council has condemned Iran's pursuit of nuclear technology – which Tehran claims is for peaceful means – and imposed sanctions on the country last month.
But Mr Ahmadinejad has shown little sign of caving in to international demands and again insisted Iran "will not be dissuaded in its drive and the Iranian nation stands united on this".
"The Iranian nation will stand up for its legal right and will not retreat even one iota to preserve its nuclear right," Mr Ahmadinejad said.
He added: "On the nuclear issue, the Iranian people will stand firm to acquire all their rights, will continue solidly to reach the summits of perfection and will raise their fists to insist on their rights."
The latest comments come after Tehran announced last week that it had now "joined the nuclear club of nations" and was able to produce nuclear fuel on an industrial scale.
The US has expressed concern at the comments and has called on Iran to "comply with its obligations to the International Atomic Energy Agency (IAEA) and UN security council".
Iran yesterday said it had plans for two further nuclear power plants to be developed next to the Bushehr plant in the south of the country.
The deputy head of the Atomic Energy Organisation of Iran, Ahmad Fayyaz-Bakhsh, said that a company has invited international countries to tender for the two plants, which will each produce 1,000 to 1,600 megawatts of power.
"Certain European companies have expressed willingness to take part in the tenders," he added, according to Iran's IRNA news agency.
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