First Friday prayers after Iran's Supreme Leader backs nuclear agreement offer clues to country's political mood

Friday prayers in Tehran today was a fascinating insight into the political mood of the Iranian leadership.

It’s been over three months since the nuclear deal between Iran and six world powers, including the UK. But in the past few weeks, the political rhetoric in Tehran has been gradually and surely more strident and confrontational.

On Wednesday Iran’s Supreme Leader, Ayahtollah Ali Khamanei said he was giving his approval to it but only conditionally. He said that there would be not negotiations or talks with the US on anything outside of the nuclear deal, and accused US President Barack Obama of wanting to overthrow the Iranian government – and for good measure he spoke of how Iran would never trust the US.

That kind of sentiment was forced home in the sermons at Friday prayers. They were given by a senior cleric Ayatollah Ahmed Khatami and attended by such senior figures as the head of Iran’s Revolutionary Guards, Mohamed Ja’afari.

Ayatollah Khatami said Iran still hated the United States, and urged Iranians to resist the attempts by countries such as the US and UK. The sermon was delivered by a senior cleric within the regime and everywhere you looked there was defiance.

As the hundreds of worshippers poured out, many broke into small groups of protests, unfurling banners reading “Down with USA” and chanting “Death to America! Death to Britain”.

But this was not just rhetoric and political theatre – it is a calculated warning – because Iran is worried about the longer term commitment of the US to this deal.

The key concern which explains this hardening of Iran’s language is what happens after Barack Obama leaves the White House. He has invested hugely in the nuclear deal with Iran and it will almost certainly be his standout political legacy.

Tehran is worried that the next President will not be so committed, and worse, will try to undo or undermine the accord.

This is why Iran’s Supreme Leader was so conditional in his support for the agreement. He is effectively saying that if the next US President is not as committed to this agreement, then Iran will walk away – and will do so angrily and confrontationally.