Iran's Supreme Leader Mojtaba Khamenei said ​in a written statement on Saturday that repeated U.S. breaches of a ​memorandum of understanding ​signed by the presidents ⁠of Iran and the ​United States had ​shown that President Donald Trump's signature was "utterly worthless and devoid ​of credibility."

Washington and ​Tehran have exchanged strikes after ‌a ⁠ceasefire agreement fell apart last week, raising fears of a return ​to ​all-out ⁠war, Reuters reported.