"Today, Iran has mastered the entire nuclear fuel cycle, from start to finish, thanks to young Iranian scientists," state television quoted the president as saying.

The hardline president made the remarks at a ceremony at Khorramshahr, a port town in southwestern Iran, commemorating the recapture of the town from Iraqi forces in 1982, one of the bloodiest battles during the eight-year long Iran-Iraq war.

"The enemies are looking to plot and want to create differences among Iranians to stop us getting our rights," Ahmadinejad said.

"But if they do the slightest damage to the Iranian people, if they commit the slightest aggression, they will receive a historic slap."

Ahmadinejad's remarks came as five permanent members of the UN Security Council -- Britain, China, France, Russia and the United States -- plus Germany set to meet in London for new efforts to defuse the crisis over Iran's nuclear issue.

In an effort to persuade Tehran to give up its sensitive uranium enrichment, the EU trio -- Britain, France and Germany -- are preparing to offer a package of incentives in trade, technology and security to Iran.

But Iran has rejected the offer from the EU trio, insisting that its right to enrich uranium is not for negotiation.

Washington has accused Tehran of trying to develop nuclear weapons under the cover of civilian nuclear energy program, which was rejected by Tehran, saying its nuclear program is only aimed at making fuel for nuclear power plant.