Broadcaster and journalist Lauren Booth, 43 - Cherie Blair’s half-sister - said she now wears a hijab head covering whenever she leaves her home, prays five times a day and visits her local mosque ‘when I can’.
She decided to become a Muslim six weeks ago after visiting the shrine of Fatima al-Masumeh in the city of Qom.
‘It was a Tuesday evening and I sat down and felt this shot of spiritual morphine, just absolute bliss and joy,’ she told The Mail on Sunday.
When she returned to Britain, she decided to convert immediately.
‘Now I don’t eat pork and I read the Koran every day. I’m on page 60. I also haven’t had a drink in 45 days, the longest period in 25 years,' she said.
'The strange thing is that since I decided to convert I haven’t wanted to touch alcohol, and I was someone who craved a glass of wine or two at the end of a day.’
Refusing to discount the possibility that she might wear a burka, she said: ‘Who knows where my spiritual journey will take me?’
Before her awakening in Iran, she had been ‘sympathetic’ to Islam and has spent considerable time working in Palestine. ‘I was always impressed with the strength and comfort it gave,’ she said of the religion.
Miss Booth, who works for Press TV, the English-language Iranian news channel, has been a vocal opponent of the war in Iraq.
In August 2008 she travelled to Gaza by ship from Cyprus, along with 46 other activists, to highlight Israel’s blockade of the territory.
She was subsequently refused entry into both Israel and Egypt.
In 2006 she was a contestant on the ITV reality show I’m A Celebrity . . . Get Me Out Of Here!, donating her fee to the Palestinian relief charity Interpal.
She said she hoped her conversion would help Mr Blair change his presumptions about Islam.
During her visit to Iran last month, Booth wrote a public letter to Mr Blair asking him to mark Al-Quds (Jerusalem) day - a protest at Israel's occupation of Palestine.
The missive was a bitter attack on the former Prime Minister, who is now a Middle East envoy working for peace in the troubled region.
'The men, women and children around me withstood a day of no water and no food (it’s called Ramadan, Tony, it’s a fast),' Booth wrote.
'Coping with hunger and thirst in the hundred degrees heat, as if it were nothing. They can withstand deprivation in the Muslim world.
'Here in Iran they feel proud to suffer in order to express solidarity with the people of Palestine. It's kind of like the way you express solidarity with America only without illegal chemical weapons and a million civilian deaths.'
She adds: 'Your world view is that Muslims, are mad, bad, dangerous to know. A contagion to be contained.
'In the final chapter [of his autobiography] you say we need a "religious counter attack" against Islam. And by "Islam" you mean the Al Quds rallies, the Palestinian intifada (based on an anti Apartheid struggle Tony, NOT religious bigotry), against every Arab who fails to put their arms in the air as the F16 missiles rain on their homes and refugee camps and sing a rousing chorus of ‘Imagine all the people...’
Booth moved to France with her family - husband Craig Darby and two daughters Alexandra and Holly in 2004.
Her husband was seriously injured in a motorcycle accident in April 2009 when he was drunk and not wearing a helmet.
He suffered a severe brain injury, a fractured neck, damage to his spine and several broken ribs and was in a deep coma for two weeks.
The 42-year-old had to learn how to walk and talk again. He lost much of his memory, has sight problem and cannot work.
The couple decided to move back to Britain to help his recovery and reduce the amount of time Booth has to work away from home.
Booth took part in I'm A Celebrity... Get Met Out of Here! in 2006 alongside Myleene Klass and Jason Donovan, finishing ninth.
Of her relationship with the Blairs, she said at the time: 'I'm happy to criticise them politically if they deserve it but that on a personal level we get on fine.'
Mr Blair was famously told not to 'do God' by his spin doctor Alistair Campbell while he was Prime Minister.
But on leaving office, he converted to Catholicism after starting to go to Mass - saying later that it was his wife who spurred his decision.
He said last year that it was like 'coming home' and is now 'where my heart is, where I know I belong'.
Ref: http://www.dailymail.co.uk/news/article-1323278/Tony-Blairs-sister-law-Lauren-Booth-converts-Islam-holy-experience-Iran.html#ixzz13J5WvcbF