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So there's been a huge amount of activity in the last 10 days which have really heightened tensions and led to fears that there's a risk of the US and Iran sliding to war. One of the key allegations the Trump administration makes against Tehran is that it arms and supports Shia militias in Iraq, in Syria, and in Lebanon, and in Yemen.
The key question we don't know is what Donald Trump actually wants. Both the US and Iran insist they don't want to go to war. But at the same time, in his administration John Bolton and Mike Pompeo are known hawks on Iran. And the US officials keep talking about escalatory action. They keep talking about threats from Iran. But they've actually given no details at all.
Behind all this is questions and concerns about whether the nuclear deal Iran signed in 2015 is about to collapse. Last week President Hassan Rouhani, the Iranian leader, announced that Tehran would stop complying with certain elements of the 2015 accord. Iran has continued complying with the deal one year after Mr Trump unilaterally withdrew the US from the deal. The pressure of US sanctions and US threats to penalise anybody seen to be doing trade with Iran has meant it's very, very difficult for the European countries to ensure that financial and trade links with Iran are maintained, leaving Iran in the deal with actually no dividend for continuing to comply with it.
So there's a lot of speculation about actually what is the US trying to do, what information does it have, and where will this go.