The newly-elected Pope Francis is set to have lunch with his predecessor, Emeritus Pope Benedict, in what is believed to be a pontifical first.
Pope Francis will be flown by helicopter to his summer residence at Castel Gandolfo for the private lunch.
Benedict has lived at the lakeside castle south of Rome since last month, when he became the first pope in 600 years to resign, citing ill health.
Cardinal Jorge Maria Bergoglio was elected to succeed him on 13 March.
There is no public record of any previous meeting between a Pope and a former Pope as usually a new head of the Catholic Church is only elected upon the death of his predecessor, says the BBC's David Willey in Rome.
Although there were periods in the middle ages when there was more than one pope, after disputed elections, there is no precedent in modern times for a sitting Pope sitting down for lunch with the pontiff he succeeded.
Pope Francis has spoken by telephone to Benedict, who watched his successor's inauguration Mass on Tuesday on television from his temporary home at Castel Gandolfo, 24km (15 miles) south-east of Rome.
The pope emeritus is expected to stay on at the papal summer residence until new accommodation being prepared for him inside the walls of Vatican City is ready at the end of April.
For his part, Pope Francis will begin the Church's most important liturgical season on Sunday with a Palm Sunday Mass in St Peter's Square.
He will then lead six more liturgies during the week, culminating with the Easter Sunday Mass and Urbi et Orbi ("To the city [of Rome] and the world") blessing.
The new Pope chose the name Francis in honour of St Francis of Assisi - the 13th century Italian saint who spurned a life of luxury to work with the poor.
He has called for the Roman Catholic Church to be closer to ordinary people, especially the poor and disadvantaged.
And, only 10 days into his pontificate, he has made some subtle but significant changes in the lifestyle of the leader of the Roman Catholic Church, says our correspondent.
He dresses very simply, preferring to wear plain black shoes under a simple white habit rather than the specially-made red leather loafers and ermine-trimmed cape worn by his predecessor.