Tokyo: The head of the United Nations nuclear watchdog said Wednesday that inspections at Iranian atomic sites were "going to happen", but did not offer a specific timeline.His comment came after Tehran and Washington signed a preliminary deal aimed at ending the Middle East war, and which cited the involvement of International Atomic Energy Agency (IAEA) in next steps on Tehran's programme.IAEA chief Rafael Grossi told reporters during a visit to Japan that the agreement "explicitly" states "nuclear activities that are going to be carried out with regards to nuclear material facilities will be supervised by the IAEA".Also Read: Trump says he would 'cancel meetings' with Iran if they deny IAEA nuclear inspections"Obviously, to do that, we will have to inspect," Grossi said.The date and location of the inspection are currently under discussion, with a decision to be made soon "in collaboration and in cooperation with the government of Iran," he said."Whether this happens today after tomorrow or in one week or in 10 days, it's important but not essential. This is going to happen."Iran said Tuesday that the UN nuclear watchdog would not be allowed to inspect nuclear sites bombed by the United States and Israel last year, rejecting Vice President JD Vance's claim that Tehran had agreed to allow inspectors back in.But US President Donald Trump said Tuesday that Iran has "fully and completely agreed" to allow nuclear inspectors to return to the country, and that US Navy forces would no longer blockade the Strait of Hormuz.