Iran's file has been sent back to the council and it now faces possible sanctions after failing to meet a demand to halt uranium enrichment, a process the West believes Tehran is developing to build atomic bombs despite Tehran's denials.
"The Security Council, in its current situation, lacks legitimacy. Its decisions are illegitimate. You (the Council) want to be the judge, the prosecutor and the executor at the same time? Those times are gone," Ahmadinejad said.
The president, who says the council serves US and British political purposes, made his latest comments to worshippers at Friday prayers in speech broadcast on state radio.
Ahmadinejad is not the most powerful figure in Iran's hierarchy of power, which gives the final word to Supreme Leader Ayatollah Ali Khamenei. But like the president, Khamenei insists Iran will press ahead with its peaceful atomic plans.
Britain's ambassador to the United Nations, Emyr Jones Parry, has said European nations hoped to circulate a draft text on sanctions against Iran to the full council early next week.
The draft text is expected to include curbs on Iran's nuclear and ballistic missile programme, which observers concede will probably not impinge on its uranium enrichment activities.
Former president, Akbar Hashemi Rafsanjani, said a move by the council against Iran would harm those who take the decision, the region and the Islamic Republic. But he did not say how they would be harmed.

RETALIATION THREAT
"We advise them not to welcome such a danger for this region and this world," Rafsanjani also told Friday prayers, adding that the government wanted to solve the dispute through talks.
Iran's chief nuclear negotiator Ali Larijani threatened retaliation on Wednesday, possibly by suspending international atomic inspections, if the United Nations imposed sanctions.
Iranian lawmakers say they are studying a bill that will oblige the government to halt inspections by the International Atomic Energy Agency (IAEA), which now carries out routine checks of Iranian facilities, if punitive steps are imposed.
Iran has shrugged off the sanctions threat, which analysts say is because the world's fourth largest oil producer believes it can cope with the modest measures mooted so far.
Western envoys say only a second or third round of penalties is likely to halt Tehran's nuclear project.
But that will depend on whether the "P5+1" group made up of the permanent members of the Security Council, the United States, Britain, China, Russia and France, and Germany can remain united on Iran.
Chinese Foreign Minister Li Zhaoxing told US Secretary of State Condoleezza Rice on Friday it would play a "constructive role" in resolving the nuclear standoff with Iran.

Copyright Reuters, 2006