Iran has begun producing nuclear fuel on "an industrial scale", the president announced during a speech to mark the first anniversary of the country's enrichment of uranium.
During a visit to the Natanz nuclear facility, Mahmoud Ahmadinejad said that that the nuclear programme was on its way to the "summit" and would not be stopped.
"The great Iranian nation, which for past centuries has been a pioneer of science, will not allow some bullying powers to put obstacles in its path of progress by influencing the international community," he said.
"Today... this country has joined the countries that produce nuclear fuel on an industrial scale."
Ali Reza Ronaghi, Al Jazeera's correspondent in Iran, said: "Ahmadinejad never misses a chance of reminding people, and the world, that Iran's nuclear programme - which it claims to be peaceful - has been under a lot of pressure and Iranian scientists have done it without help from
the outside world."
Ahmadinejad's speech confirmed an announcement by the head of the country's atomic energy organisation, who alo said that Iran had started mass-producing the centrifuges needed for the enrichment of uranium.
"Today, with the start of mass-producing centrifuges and the start of uranium enrichment on an industrial phase, another step was taken for the flourishing of the Islamic republic," Gholam Reza Aghazadeh said.
Ali Larijani, Iran's chief nuclear negotiator, told reporters that 3,000 centrifuges were being used to enrich uranium at the facility.
Experts say Iran could make enough nuclear material for one nuclear bomb a year with 3,000 machines.
Larijani also threatened to withdraw from the nuclear non-proliferation treaty if Tehran were subjected to further international pressure over the issue.
"If they pressure us further we will have no choice but to reconsider our membership of the NPT, as parliament has ruled," he said.
The United Nations Security Council has passed two resolutions since December imposing sanctions on Iran over its nuclear programme.
The International Atomic Energy Agency, the UN's nuclear watchdog, has said it has gaps in its knowledge about Iran's plans that must be filled before it can decide whether or not the programme is peaceful.
The IAEA is pushing Tehran to agree to let it install cameras in the underground section of the Natanz plant to monitor Iran's work, but Iran says such surveillance measures go beyond the basic safeguards it is required to allow.
"I found the speech coming from Ahmadinejad reasonably moderate, many people expected he would adopt a much tougher tone ... and he
did not enter into very fine detail of what exactly Iran has achieved," Professor Sadegh Zibakalam, a political analyst from Tehran University,
told Al Jazeera.
"I think the gist of Ahmadinejad's speech was defiant against the recent security council sanctions ... he was definitely saying we will not be
coerced, we will not be intimated by the United States and the Security Council."
To mark the nuclear celebration, state television broadcast programming on how enrichment is carried out and detailed how many nuclear plants countries such as the United States and France possessed.
It said atomic progress was a source of "national pride of the highest degree".
Güncelleme Tarihi: 20 Eylül 2018, 18:16