They threaten to harm us. If that happens, they will definitely receive a powerful counterattack, he says in a speech.
The ayatollah's threat comes after the US President Donald Trump warned Tehran that rejecting the American demands in the nuclear energy issue would have consequences.
If they (Iran) do not agree to a deal, it will be bombed, and the bombings will be on a scale they have never seen before, Trump told NBC News on Sunday.
Trump's threat was in response to Iran's President Masoud Pezeshkian's stated no to direct negotiations with the US.
Earlier, Trump had threatened both economic and military actions against Iran if Tehran opposes a deal on the country's nuclear energy program.
During his first term, Trump withdrew the US from the JCPOA nuclear energy agreement with Iran. The agreement involved exchanging sanction relief for limitations on Iran's nuclear technology program.
Since then, several warnings have been issued that Iran is on its way to producing nuclear weapons, something the regime in Tehran denies.
