The news conference was the second of Ahmadinejad's presidency
At a rare news conference in Tehran, Mr Ahmadinejad said they were needed only by people who "want to solve everything through the use of force".
The president defended Tehran's recent move to restart nuclear research, which has sparked international condemnation.
Iran says it has a right to peaceful nuclear technology and denies that it is covertly seeking to develop weapons.
The US, UK, France and Germany are threatening to refer Iran to the United Nations Security Council, which could impose sanctions.
Leaders who believe they can create peace for themselves by creating war for others are mistaken
President Ahmadinejad
Excerpts: Ahmadinejad remarks
But the president said a referral would not end its nuclear plans.
"If they want to destroy the Iranian nation's rights by that course, they will not succeed," he said.
Tehran has said it will stop snap UN inspections of nuclear sites if its case is sent to the Council.
The crisis intensified this week when Iran removed seals at three nuclear facilities, ending a two-year freeze.
'Arrogant rulers'
Mr Ahmadinejad told reporters Tehran pursued an active foreign policy which sought peace, based on justice.
IRAN'S NUCLEAR STANDOFF Sept 2002: Work begins on Iran's first reactor at Bushehr Dec 2002: Satellites reveal Arak and Natanz sites, triggering IAEA inspections Nov 2003: Iran suspends uranium enrichment and allows tougher inspections June 2004: IAEA rebukes Iran for not fully co-operating Nov 2004: Iran suspends enrichment under deal with EU Aug 2005: Iran rejects EU plan and re-opens Isfahan plant Jan 2006: Iran re-opens Natanz facility
In depth: Nuclear fuel cycle Iranian press scorns criticism
He criticised the "double standards" of Western countries which already had nuclear weapons, and attacked "arrogant rulers" for causing suffering.
"Leaders who believe they can create peace for themselves by creating war for others are mistaken," he said.
A few had a "medieval mindset" and sought to deprive Iran of valuable technology, without evidence of wrongdoing, he added.
Mr Ahmadinejad sparked international outrage with his hardline stance towards Israel, following his election last June.
He repeated both his attacks and calls for a referendum for Palestinians to choose their future political fate.
"(Israelis) have no roots in Palestine and almost all are immigrants," he said.
"Let the nation of Palestine decide among themselves."
Diplomatic divisions
Western countries are now seeking to persuade other members of UN nuclear watchdog the International Atomic Energy Agency (IAEA) to agree to refer Iran to the Council.
The Iranians crossed a line by reactivating nuclear facilities the UN had shut
Albert Arnim, Dresden, Germany
Send us your views Head-to-head: nuclear crisis
European, Russian, Chinese and US officials are due to meet in London on Monday, when they are expected to set a date for the crucial IAEA meeting.
On Friday, US President George W Bush and German Chancellor Angela Merkel agreed that the crisis should be resolved through peaceful means.
Washington, Israel and many European powers distrust Iran, partly because it had kept its nuclear research secret for 18 years before it was revealed in 2002.
Since last August, Iran has resumed all nuclear activity apart from enrichment, which can produce fuel for power stations or, under certain conditions, for bombs.
Tehran has always said it has the right under the nuclear Non-Proliferation Treaty - which it has signed - to research nuclear energy for peaceful purposes.
Map highlighting Iran
Iranian president Mahmoud Ahmadinejad spoke out in a rare news conference on Saturday against statements made by Europe and the United States, saying that if any country refers it to the U.N. Security Council over its nuclear program, that it will end their voluntary compliance with surprise inspections and other nuclear cooperation with the U.N. nuclear watchdog, the IAEA. He also warned that Europe will lose the chance of reconciliation if it pursues sanctions.

President Ahmadinejad said that even if Iran is referred to the Security Council for possible sanctions, the action would still not stop its nuclear program. "They keep on threatening us that we have to either accept what they say or they will send us to the Security Council," President Mahmoud Ahmadinejad said during a news conference in the Iranian capital of .

Iran's statements came as Europe and the U.S. began to build support for reporting Iran to the U.N. Security Council. However, China has been cautious and has warned the move could only escalate the confrontation.

Meanwhile, President George W. Bush, and Chancellor Angela Merkel, urged U.N. intervention. "The world needs to send a common message to Iran that their behavior...is unacceptable," Bush said.

The U.S. and Europe continue to have growing concerns that Iran is trying to produce nuclear weapons.

On Tuesday, Britain, France and Germany issued a statement declaring that 2 1/2 years of tense negotiations with Tehran were a "dead end" and urged the U.N. Security Council to intervene.
The U.N. Security Council
Iranian Foreign Minister, Manoucher Mouttaki, said to the press yesterday that "the West will bear the consequences if Iran is sent to the Council. Iran does not need to have permission from any country. It is our legal right to have nuclear energy."

In response the Bush administration, along with Chancellor Angela Merkel, said that they "cannot allow countries such as Iran to blackmail peace-loving countries like themselves."

Iranian President Mahmoud Ahmadinejad said that his "country does not need nuclear weapons. They are needed only by people who want to solve everything through the use of force." He then went on to say, "Leaders who believe they can create peace for themselves by creating war for others are mistaken."

Tehran has always said it has the right under Article VI of the  — which the nation has signed but not ratified — to research nuclear energy for peaceful purposes.