“They threaten to do mischief,” Khamenei said of Trump’s latest threat, during a speech on Eid al-Fitr, the holiday marking the end of the Muslim fasting month of Ramadan. “If it is carried out, they will definitely receive a strong counterattack,” he said.

Iran and Russia took decisively different approaches in response to President Donald Trump's threats as Tehran vowed action against any "mischief" while the Kremlin remains tight-lipped.

Iran's Supreme Leader Ayatollah Ali Khamenei said on Monday the U.S. would receive a strong blow if it acts on Trump's threat to bomb unless Tehran reaches a new nuclear deal.

Iranian state media is reporting that Iran has placed all of its missiles on launchers in response to a potential U.S. attack.

Russia has warned that strikes against Iran's nuclear infrastructure would have "catastrophic" consequences, after U.S. President Donald Trump threatened to bomb Iran unless it came to an agreement with Washington over its nuclear program.