Hello and welcome to NewsHour.
It's coming to you live from the BBC World Service studios in central London.
I'm Tim Franks.
And we're beginning with a promise, a promise delivered by the Trump administration,
in this case, the Treasury Secretary rather than the President.
But even without the capital letters and exclamation marks beloved by Mr Trump,
this promise is striking and it's unequivocal.
Today, says Scott Besant, begins an economic D-Day,
the single greatest financial offensive ever marshalled against an adversary.
Mr Besant...
Is talking about a new suite of sanctions against Iran.
He might think that there couldn't really be further sanctions left to impose,
but this time, this time, he says it really will be different
because the US will properly go after any other countries which continue to trade with Iran.
As he puts it, our objective is to sever every economic lifeline that sustains the tyrannical regime.
So today we'll try to work out what effect this might have on the regime
and on ordinary Iranians and also whether it's even feasible for the US to do.
Omid Khazani is a journalist for the LA Times.
He's based in Tehran.
How does he think people are viewing the threat of an ever tighter economic squeeze?