Iran has every right to pursue nuclear power. It is a matter of national sovereignty. We should never have signed the Non-Proliferation Treaty in 1968 – it was based on an unfair bargain. I believe that now, and I believed it more than 40 years ago, when the Shah of Iran, Mohammed Reza Pahlavi, put me in charge of creating the country's nuclear programme.

In 1965 I had just finished studying reactor physics in Switzerland and arrived back in Iran. I had no job, no real plan of action – I had been away for 15 years. At the University of Tehran, the government was building a nuclear research reactor with US assistance through Eisenhower's “Atoms for Peace” programme. One day, I read in the paper that work had stopped because of a lack of expertise. An angry Shah had ordered the chairman of the National Planning Organisation to find a way to finish the project.

So I put all my diplomas in a bag and went to the chairman's offices. His secretary didn't want to let me in, but I said that if she told her boss there was a young Iranian at reception who knew about the atom, he would see me. He saw me. I detailed my qualifications and experience, and I still remember the relief on his face: “God has sent you through the window to us,” he said.