Justin Welby talked to Julie Etchingham during his latest visit to Rome about what links and what divides the Catholic Church and the Anglican Community

It has been a whirlwind 48 hours in Rome, and Archbishop Justin Welby seems thoroughly invigorated by it. Fresh from private discussions with Pope Francis, and a Mass celebrated in St Peter’s, we meet in the very British surroundings of Villa Wolkonsky, residence of the UK ­ambassador to Italy, to talk about both the joys and the pains of the historic visit.

On his right hand is the glittering ring given 50 years ago by Pope Paul VI to Michael Ramsey, one of Justin Welby’s predecessors as Archbishop of Canterbury, to seal a turning point in the relationship between the Roman Catholic Church and the Anglican Communion. It is a large, square, green stone divided by a gold cross and studded with four diamonds – rather unwieldy on Archbishop Welby’s slim right hand, and you occasionally catch him turning it in his fingers.

There is little doubt that the personal ­connection between Welby and Pope Francis is a key driving force in these renewed efforts for Christian unity. Those of us who saw the pair before they spent time in private conversation witnessed them roaring with laughter at a shared joke. So what insight can the archbishop offer into their friendship?