Iran’s Supreme Leader Ayatollah Ali Khameini claims the country has no interest in producing nuclear weapons.

However, he told the Non-Aligned Movement summit for heads of state on Thursday, Iran will continue to pursue its nuclear technology development program. Khameini insisted Iran’s nuclear activities are aimed at developing peaceful atomic energy.

“Our motto is nuclear energy for all, and nuclear weapons for none,” he said.

It is Khameini who holds the ultimate power over whether or not nuclear weapons are created — and used — or not, in Iran.

United Nations Secretary-General Ban Ki-moon, who is attending the summit, told Iran’s leadership on Wednesday to stop threatening Israel, his spokesman said. The U.N. chief urged Iran to prove in concrete terms the country’s nuclear activities are peaceful.

In addition to his meeting with Khameini, Ban met with Iranian President Mahmoud Ahmadinejad, Parliament Speaker Ali Larijani, and Supreme National Security Council Secretary Saeed Jalili, spokesman Martin Nesirky said.

Khameini fiercely criticized the U.N. Security Council in his speech, calling the international body an illogical, unjust and defunct relic of the past used by the U.S. “to impose its bullying manner on the world.”