Peter Oborne writes:
Britain's prime minister has been fighting a valiant, losing battle to rescue British relations with Iran in the wake of US President Donald Trump's reckless attempts to wreck them.
But last week Theresa May was dealt a devastating blow to her authority after several Tory MPs defied her by going to Paris for a meeting designed to promote regime change inside Iran.
This event is the latest sign that the prime minister and her foreign secretary, Boris Johnson, are facing a mutiny over Iran.
No regime change
Former cabinet minister Theresa Villiers was among senior Tories who travelled to Paris last week to hear Rudy Giuliani, former mayor of New York and Trump's highly influential lawyer, call for the downfall of the Iranian government.
This meeting was a direct defiance of British government policy, which aims to save the Iran nuclear deal intact, and is against engineering a change of government in Iran.
Indeed, Johnson assured Parliament in May that "I do not believe that regime change in Tehran is the objective that we should be seeking."
Three Tory MPs – along with one Labour MP – travelled to the event, organised by the National Council of Resistance of Iran, a front organisation for Mojahedin-e-Khalq Organisation (MEK), once listed by the US as a terror organisation.
There is no question that these reflect a powerful and vocal body of sentiment inside the Conservative Party. This has been clear ever since the House of Commons debate on Iran on 9 May.
The overwhelming majority of Conservative MPs favoured Trump’s policy of dismantling the JCPOA - and condemned May's policy of keeping it.
The overwhelming majority of speakers (I calculate 19) in the debate spoke out against the JCPOA, and only five were explicitly in favour.
Those opposing the JCPOA included former defence secretary Michael Fallon and former cabinet minister Stephen Crabb. Former leader Iain Duncan Smith also spoke out against the deal in a Commons debate later in May.
These interventions raise troubling questions about the judgment and the allegiance of Tory backbenchers.
So yesterday I approached the three Tory MPs who attended last weekend's conference in Paris with a series of questions.
I asked them:
Who paid for and authorised their attendance at the MEK conference?
Why as a signatory for the JCPOA are members of the current government pushing for the toppling of a signatory nation?
Is it the government's policy to pursue regime change in Iran? Do they think the MEK actually have popular legitimacy in Iran?
There was no reply from any of them.
Tory MP Matthew Offord's office even hung up the phone on MEE rather than answer legitimate questions.
Then I asked the Conservative Party's central office if they knew about and had given permission for the Tory MPs to attend. Once again – no response. A wall of silence from all involved.
The support inside the Tory party for the MEK looks like a sign of a party that has taken leave of its senses.
Here is an organisation with a proven history of terrorism, including against Western interests.
Though founded by the husband and wife team of Massoud and Maryam Rajavi, the MEK reportedly forces members to divorce and give up their children to foster care so as to avoid the distraction of familial love.
It has other characteristics of a cult. For instance, former members also describe participating in regular public confessions of their sexual fantasies.
The clear ambition of last week's meeting was to use the MEK as a vehicle to bring down the current government in Iran.
No coherent plan
This conference in Paris comes against a menacing international background.
The Trump administration is working flat out to destabilise Iran through the installation of brutal economic sanctions.
Some observers believe the conduct of the US is very similar to the CIA destabilisation campaign aimed at Iranian prime minister Mohammad Mosaddeq in 1953.
The CIA then at least had a clear alternative future in mind for Iran – restoration of the shah under American tutelage. In American terms, this policy was a success for the next two decades.
Trump’s people have no coherent plan for Iran.
The cultivation of the MEK – an opposition group based outside Iran and thought to be supported by a rackety coalition of international backers including Saudi Arabia – has strong echoes of Ahmed Chalabi's Iraqi National Congress in the run-up the Iraq invasion in 2003.
Chalabi was hugely influential in convincing the neo-conservative backers of the Iraq invasion that he had strong support inside Iraq and could turn the country into a model state. He was proved wrong.
Giuliani boasted how Trump had "turned his back on that very dangerous nuclear agreement with Iran".
He further boasted that recent popular protests inside Iran have been orchestrated from outside the country, insisting that they "are not happening spontaneously".
And he ended his speech exclaiming: "Next year, at this time, I want us to have this convention in Tehran!"
Ominously, last year's chief speaker at the Paris conference was John Bolton, one of the most eloquent advocates of the Iraq invasion, who has now become Trump's national security adviser.
This means that Trump has decided to repeat – in a larger and more dangerous country – all the errors of American policy in Afghanistan and Iraq.
He intends to hand over Iran to politicians with no democratic legitimacy – and no more loyalty to the United States and Western values than America's former protégés, the Taliban and al-Qaeda.
British MPs should be ashamed of helping him.