Iranian officials said Tuesday that new U.S. sanctions mean “closing the doors of diplomacy” between the two countries amid increasingly acrimonious relations.The sanctions, which target the country's supreme leader, Ayatollah Ali Khamenei, and other top Iranian officials, are “outrageous and idiotic,” President Hassan Rouhani said.“You sanction the foreign minister simultaneously with a request for talks,” Rouhani complained, before calling the White House "mentally retarded."“Trump’s government is annihilating all the established international mechanisms for keeping peace and security in the world,” Iranian Foreign Ministry spokesman Abbas Mousavi wrote on Twitter, calling the Trump administration "desperate."In response, President Trump issued a warning that attacking American targets will result in disaster for Iran."The wonderful Iranian people are suffering, and for no reason at all. Their leadership spends all of its money on Terror, and little on anything else," Trump wrote Tuesday on Twitter. “Iran’s very ignorant and insulting statement, put out today, only shows that they do not understand reality. Any attack by Iran on anything American will be met with great and overwhelming force. In some areas, overwhelming will mean obliteration.”Last week, Trump called off airstrikes planned as retaliation for Iran's downing of an unmanned American drone with just minutes to spare. He later cited concerns about the potential casualties, which he said would have been around 150, in justifying the decision.Tensions with Iran have been escalating ever since the White House backed out of the 2015 nuclear weapons deal last year, brokered by the Obama administration and consistently disparaged by Trump.