Leo Blair nibbled sweets as his family celebrated Mass in the Pope’s private chapel on a two-day visit to the Vatican in February 2003, shortly before the start of the Iraq war, the book reveals.

While his father was uncomfortable about his meeting with Pope John Paul II, who was opposed to the war, the “real interaction” was between the Pope and Leo, then aged two and a half, Blair Unbound reveals in a detailed account of the meetings.

The Pope received the Blairs in his library at their first meeting on Saturday February 22. Blair was the first to be brought in, alone, for an audience of 20 minutes. Cherie then joined them for another ten minutes, before the children were summoned.

The following extract describes what happened: “Cherie was more at ease than her husband during the audience and seemed quite unfazed by Leo scampering around the room. But the Prime Minister seemed off his game. To colleagues he appeared discomforted by this personal audience. John Paul II was a known critic of the war.

“The Pope acknowledged that Blair’s intentions were good, but he would go no further. One aide formed a clear impression that the Pope had ‘laid into him about Iraq, making clear that he was against the coming war’. That afternoon ... Blair remained troubled and out of sorts.

“Sunday proved less angst-ridden, with a second encounter with the Pope for morning Mass. The intervention of Cardinal Murphy O’Connor had been significant in persuading the Vatican to hold the Mass.

“As late as Saturday night it was still not clear whether Blair himself would receive communion. In the end it was decided that the Pope’s private secretary should give communion to all in the party, including Blair.

“The second issue involved less soul-searching: should toddler Leo attend? Blair, in particular, was nervous at the prospect of keeping Leo quiet for that length of time. The answer back from the Pope’s private office, and, Number 10 thought, from the Pope himself, was strongly that Leo should be there.

“The service was held in the Pope’s private chapel ... Blair and Cherie sat in pews in the front on the left with the family immediately in front of them on stools. Leo was placed at the back of the chapel with his nanny and a little bag of sweets. ‘Every now and then you would hear this little echo ... there’d be a rattle of plastic and a sweet would go into his mouth, and there’d be silence again for three or four minutes,’ said an observer.”

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