Three days ago, ties between the US and Iran took a significant turn for the worse.
Donald Trump pulled the US out of a multi-country deal that suspended sanctions on Iran while limiting its nuclear activities. After saying the deal was "defective at its core", he placed more sanctions on Iran.
Iran responded with frustration, but it now appears to be engaging in a more off-the-cuff manner.
On Friday, Iran's Supreme Leader Ayatollah Ali Khamenei was pictured in a post on his Instagram feed at the Tehran Book Fair.
Nothing unusual there, but in one image he was seen reading a Persian-language edition of Michael Wolff's book Fire and Fury, which claims that life in the White House is chaotic.
The US president described the book as "fiction" and Mr Wolff as a "fraud".
When the book was released in January, it was described as a "bombshell" by commentators as it raised doubts over Mr Trump's mental health.
It claimed that Mr Trump pursued friends' wives and that his daughter Ivanka would mock his hairstyle behind his back.
The photo was posted just days after Iran's President Hassan Rouhani appeared to troll the US in the wake of Mr Trump's decision to pull out of the deal.
The deal with Iran's government was signed by Mr Trump's predecessor, Barack Obama.
It was agreed between Iran and the five permanent members of the UN Security Council - the US, UK, France, China and Russia - plus Germany.
On Wednesday, Ayatollah Khameni said Mr Trump had "made a mistake" in deciding to leave a multi-country nuclear deal.
"I said from the first day: don't trust America," Mr Khamenei said.
On a visit to Tehran's book fair - which began on 2 May and closes on Saturday - the Shia religious leader cut a jovial figure as he spoke with store-holders and read books..