Iran and US trade barbs ahead of new sanctions

The United States on Monday was due to tighten sanctions on Iran as the two countries traded barbs in a tense standoff sparked by Washington's withdrawal from a nuclear deal. Both nations say they want to avoid going to war, but tensions have spiralled as a series of incidents, including attacks on tankers and the shooting down of a US drone by Iran in the Gulf, raised fears of an unintended slide towards conflict. On Sunday, Iran's Foreign Minister Mohammad Javad Zarif said a US-made MQ9 Reaper "spy drone" -- also widely used for carrying out military strikes -- had encroached his country's airspace on May 26.