Former Archbishop of Canterbury Rowan Williams is leading a campaign urging western countries to put religious minorities at the heart of any future deal with Iran.

Lord Williams joins the former Bishop of Oxford John Pritchard, the Bishop of Bristol Mike Hill, the Bishop of Burnley Philip North and dozens of other faith leaders in the UK and US to stress the 'harassment and persecution' of Christians in Iran under 'the ruling theocracy'.

The petition calling on governments to make the end to oppression of religious minorities a precondition before any deal with Iran has been signed by more than 90 religious leaders ahead of a major conference in Paris on Saturday.

Tens of thousands are expected to attend the 'Free Iran' event on July 1 to highlight the levels of persecution under President Hassan Rouhani.

'While the majority of the victims of the Iranian regime's rights abuses are Muslims, members of religious minorities, including members of the Christian and Jewish faiths, have been specifically targeted over their personal religious beliefs over the years,' the faith leaders write.

'The situation of religious minorities have deteriorated in recent years, including during the tenure of President Hassan Rouhani. Scores of Iranian pastors are languishing in prisons solely for their beliefs,' they add, claiming children's textbooks encourage hatred of Jews for taking Muslim lands.

'In such circumstances, we call on all countries to consider the deplorable situation of human rights in Iran, particularly the painful situation of religious minorities, in navigating their relations with Iran. We urge them to precondition improvement of those relations on a cessation of oppression of minorities and on a halt to executions in Iran.'

The signatories point to statement by the UN secretary-general António Guterres who said in March 2017: 'Members of religious and ethnic minorities have continued to endure abuse and discrimination and face persecution, including arrest and imprisonment, expulsion from educational institutions, denial of economic opportunities, deprivation of the right to work, the closure of businesses and the destruction of religious sites, such as cemeteries and prayer centres.'

This comes after the US Commission on International Religious Freedom's 2017 report said: 'During the past year, the government of Iran engaged in systematic, ongoing, and egregious violations of religious freedom, including prolonged detention, torture, and executions based primarily or entirely upon the religion of the accused.

'Since President Hassan Rouhani was elected in 2013, the number of individuals from religious minority communities who are in prison because of their beliefs has increased.'