Iran's president has challenged US President George W Bush to a live TV debate on world affairs.
Mr Ahmadinejad again insisted Iran's programme was peaceful
Mahmoud Ahmadinejad accused the US and UK of abusing their "special privileges" and said a debate would let both sides air their views uncensored.
The White House called his suggestion a "diversion" from global concerns over Iran's nuclear programme.
Mr Ahmadinejad was speaking two days before a UN deadline for Iran to halt work on its nuclear programme.
He said Tehran had proposed a framework for further talks but said no-one could stop Iran having a peaceful programme.
"Peaceful nuclear energy is the right of the Iranian nation," he told a news conference.
"The Iranian nation has chosen that [course] based upon international regulations, it wants to use it and no-one can stop it."
He said Iran's response to an incentives package, offered by six nations in exchange for a halt to its nuclear programme, was an "exceptional opportunity" to resolve the dispute.
When asked if Iran would halt enrichment, he said any kind of dialogue "should be based upon the certain rights of the Iranian nation".
"I suggest holding a live TV debate with Mr George W Bush to talk about world affairs and the ways to solve those issues," Mr Ahmadinejad told reporters.
"The debate should be uncensored in order for the American people to be able to listen to what we say and they should not restrict the American people from hearing the truth."
Iran shows no sign of halting its nuclear work
Iran and many other nations "are against America's practices in managing the world", he said, calling such practices unjust.
He accused both the US and UK of taking advantage of their "special privileges", saying he thought they were the "the origin of all disturbances in the world".
And he also questioned their right to a veto in the UN Security Council. "Isn't it time that international relations are founded on democracy and equal rights of the nations?" he went on.
But he did not rule out talks with the US in future, if certain conditions were met.
Mr Ahmadinejad's challenge to President Bush was dismissed by the White House.
"Talk of a debate is just a diversion from the legitimate concerns that the international community, not just the US, has about Iran's behaviour," White House spokeswoman Dana Perino was quoted by Reuters news agency as saying.
Iran has been given until 31 August to halt uranium enrichment - a possible route to nuclear weapons.
Earlier this week, Tehran had offered "serious talks" in response to a package of incentives put forward by the five permanent UN Security Council members and Germany.
Washington has proposed implementing sanctions if Iran fails to meet the deadline, while Russia has said such a move would be premature.
Mr Ahmadinejad said it was "unlikely" the Security Council would take action against Iran, and said "sanctions are not an issue".
"We have said everything in our response. I think the time to use the instrument of the Security Council has expired," he said.