The US President Donald Trump warned his Iranian counterpart Hassan Rouhani against threatening the US, adding that there could be severe consequences.At a ceremony attended by Iranian diplomats, Rouhani had asserted that his country was not seeking to start hostilities with the US, but it would not shy away from a fight, Efe news reported."To Iranian President Rouhani: NEVER, EVER THREATEN THE UNITED STATES AGAIN OR YOU WILL SUFFER CONSEQUENCES THE LIKES OF WHICH FEW THROUGHOUT HISTORY HAVE EVER SUFFERED BEFORE," Trump tweeted to Rouhani late on Sunday."WE ARE NO LONGER A COUNTRY THAT WILL STAND FOR YOUR DEMENTED WORDS OF VIOLENCE and DEATH. BE CAUTIOUS!" he added.Rouhani had said that dealing with the US does not mean surrendering and putting an end to Iran's achievements, and called Trump a liar."(Iran's) enemies must understand well that war with Iran is the mother of all wars, and peace with Iran is the mother of all peace," he was quoted as saying by the Iranian Presidency's website.In May, Trump pulled the US out of the 2015 multilateral nuclear agreement with Iran and re-imposed sanctions on Tehran, which will come into force in August.Trump has criticized the earlier pact and demanded a more aggressive one which restricts the Iranian ballistic missile program.The 2015 nuclear agreement, signed by Iran and the P5+1 Group comprising the US, Russia, China, the UK, France and Germany, limits Tehran's nuclear energy program in exchange for the lifting of international sanctions, but its future is unsure after Washington's measures.