The Most Rev Justin Welby and Pope Francis are attending a special service at the church of San Gregorio al Cielo in Rome on Wednesday to mark half a century of the city's Anglican Centre.
At the @UniGregoriana with @JustinWelby to celebrate 50 years of @AnglicanCentre.
— Edoardo (@EdoardoFanfani) October 5, 2016
So proud to be @c_of_e today. pic.twitter.com/oee1nFbaT1
Centre director, Archbishop David Moxon said: "The Anglican Centre has worked for fifty years to help Roman Catholics and Anglicans work together, pray together, study and talk together.
"The journey we are on demands the laying-down of old fears and misconceptions of each other, and the building up of a shared story together. These celebrations mark the writing of a new chapter in the history of the Christian Church."
The service, which is the third time Archbishop Welby and the Pope have met since 2013, will also see 19 pairs of Anglican and Roman Catholic bishops from across the globe consecrated.
The Anglican Centre was founded in 1966 following a landmark meeting between Archbishop Michael Ramsey and Pope Paul VI, "with the aim of promoting Christian unity in a divided world".
Speaking on Premier's News Hour Archbishop David Moxon, the director of the Anglican Centre and the Archbishop of Canterbury's Representative to the Holy See, said: "We've seen huge strides forward.
"They say God walks through history a decade at a stride and if you look at this in terms of five strides forward: we now agree on baptism, we agree of the meaning of the great thanksgiving and the Eucharist, we agree on the way we should use the Bible, we agree on mission and the Kingdom of God.
"What unites is greater than what divides and on that basis, if we believe Jesus when he said 'Father, may they all be one even as we are one,' that vision of Jesus, that call from Jesus, is to say we should work towards unity. That's the most compelling reason of all - Jesus himself."
Listen to Premier's Aaron James speaking to Archbishop David Moxon on the News Hour: