"We are not after an atomic weapon. We want to break the supremacy (of the world powers) that relies on nuclear weapons. God willing, the nation will reach this goal," he told a meeting with Iranian nuclear scientists, according to an official government statement.
"Despite what the enemy (the West) says, nuclear energy is directly linked to our national interests," Khamenei said, urging the scientists to "continue the important and substantial" nuclear work.
Khamenei's reiteration of Iran's longheld stance came after a five-strong delegation from the UN's International Atomic Energy Agency left Tehran empty-handed following two days of talks focused on suspected military aspects of Iran's nuclear programme.
The UN nuclear inspector heading the team, Herman Nackaerts, said on his return to Vienna the Iranians had not permitted the team to visit a military site in Parchin where apparently non-peaceful activities had been detected.
He also said "we could not formalise the way forward," signalling that the delegation left with no further talks scheduled. The IAEA delegation was to submit its report, "then we will have to see what are the next steps," Nackaerts said.