Father Michael Seed leans conspiratorially over a cafe table in St James’s Park and asks in his trademark flute: “Do you know where I’m having the launch party for my book?” I shake my head. “Stringfellows!” he cries, while I try not to spit out my tea.

“Is Ann Widdecombe going?” I stammer, trying to banish the tarts and vicars image of Seed and his devout, high-profile pals enjoying a night of nudie girls.

“Oh yes,” he says, “though I have only told her the party will be on St Martin’s Lane. She won’t know what it is until she gets there,” he chuckles. “I don’t think Ann will go on a pole, do you?”

Even Cherie might balk at that one, though of course the Blairs have been invited, along with Terry Wogan and Alastair Campbell. It’s the sort of evening that Seed — who has never let his hessian robe get in the way of a good time — will adore; light-hearted, drink-fuelled and abuzz with power — the opposite, frankly, of what the 52-year-old Franciscan friar expected from life.

After being abandoned by his impoverished mother as a child, he was fostered by a woman. She committed suicide, leaving him in the care of a brutal foster father in Bolton who beat and molested him in turn. The sorry saga is documented in an earlier memoir, Nobody’s Child, a book his friends begged him not to write.

“Catholic priests aren’t meant to talk about these things,” Seed explains, but he has no regrets. After his childhood traumas, he found God in his mid-teens while working at an old people’s home in Manchester. He still gets letters from nuns who had similar journeys so, on balance, thinks it’s good to share.

He was well placed to. It is 25 years since Seed first fumbled his way into Westminster as the unofficial envoy from the Catholic Church to parliament. His role gave him a quiet sort of power. He had the ear of princesses and prime ministers (nipping into Downing Street to celebrate mass for the Blairs), and was able to effect introductions at the highest level. More usually, he could be found offering spiritual succour — and a drink (or three) — to parliament’s rogues, a mob he fondly dubs “creatures”.

Naturally, this access brought fans and detractors alike. Damian Thompson, editor-in-chief of the Catholic Herald, calls him “perhaps the best listener I’ve ever met”, though other co-religionists dismiss him as “profoundly silly”.

He weaves a magic, though. Not long after he pitched up at Westminster, he started collecting scalps. John Gummer was an early Catholic convert under Seed’s guidance, but it was with Ann Widdecombe he made his name.

Widdecombe, then a social security minister and apparently a staunch Anglican, had been kicking around the bars in Westminster with Seed for a couple of years when, in 1992, the decision to ordain women priests sent her running for Rome. Her baptism was a media circus and earned Seed his unshakable soubriquet: “priest to the stars”.

He left his post at Westminster Cathedral last year but still describes his life as: “Pre-Ann Widdecombe and post- Ann Widdecombe. Though I still don’t understand why it was such a big thing. I suppose Catholicism and politics is always seen as sinister — the gunpowder plot and so on — and then there was Mr Blair, of course. But if Mr Blair had become a Methodist, what difference would it make? Or, for that matter, a Buddhist?”

Buddhism might have made headlines, I say. “Hahaha — or a Muslim! But Catholicism is still seen as subversive. It’s silly, and maybe a British thing, though we had a Catholic Speaker until recently — Michael \, who I knew in the mid-Eighties.”

Seed can gossip with the best of them, wearing a wide-eyed, butter-wouldn’t- melt expression throughout. In fact, I’m not even sure he’s that interested in politics. Loosely right-wing, it’s the politicians who fascinate him. “In life, there’s the good, the bad, the ugly . . . and politicians,” he laughs. “They need a thick skin. If you’re wimpish or sensitive — like I am, actually — you don’t survive.”

What sort of problems do MPs come to you with? “Happiness,” he says, “and wanting to be appreciated for who they are rather than how the public views them. The real problem is they all want to be prime minister.”

Seed sometimes felt like the only man on Whitehall whose dial was set to receive rather than broadcast. No wonder he was such a hit. For all his “wimpishness”, he had his share of run-ins. Widdecombe inadvertently got him into hot water when a “drunk” female MP, a cradle Catholic, took to verbally abusing Seed over the phone in the middle of the night for bringing Widders into “her” church.

So you’ve made enemies? “Of course. You can’t help not.”

Actually, he’s terrified of causing offence. His modus operandi is firmly “God’s the judge, not me”. The nearest he gets to proper scandal is in discussing allegations that he converted his great friend Alan Clark on his deathbed. “He was administered to both by Reg Humphreys, the Anglican vicar of Saltwood, and by me,” he says carefully. “It’s all in God’s hands, and that’s that. I’ve just got to respect Jane [Clark's widow].”

Watching him drink his coffee in the morning sun, talking of prime ministers, palaces and trips on private jets with his fancy friends, it’s hard to reconcile Seed’s swanky life with his toxic childhood. He says the contrast used to worry him too — he fretted about the backlash from colleagues in the clergy — but he’s over that now.

“I’ve stopped minding about them. I really don’t give two hoots any more. Some days I used to want to run away, to escape. Most think I’m just some silly person — and I am. But I rejoice in my silliness. It’s fine. I think they’re dull.”

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