Trump threatens Iran with 'obliteration' in angry tweet
Trump threatened "overwhelming" response and could bring "obliteration" if the US was attacked.
"Any attack by Iran on anything American will be met with great and overwhelming force. In some areas, overwhelming will mean obliteration," he tweeted.
"Iran leadership doesn't understand the words 'nice' or 'compassion', they never have. Sadly, the thing they do understand is Strength and Power, and the USA is by far the most powerful Military Force in the world, with 1.5 Trillion Dollars invested over the last two years alone," he tweeted.
Washington and Tehran nearly went to war following last week's downing of a US surveillance drone.
Iran claimed it was in its airspace, while the US said it was outside, Trump pulled back from plans to retaliate with military strikes on Iranian targets, when he "realised" there would be scores killed.
In retaliation he slapped a fresh round of tough sanctions on Iran, including on its Supreme Leader Ayatollah Ali Khamenei and top military chiefs.
Iran said it would abandon any promises it made under the 2015 nuclear deal signed with world powers and would not hold talks with the US. Washington withdrew from that deal last year.