Archbishop Paul Gallagher, who arrived in Canberra this month and is to present his credentials to the Governor-General on April 30, said he could only comment in his private capacity as a Catholic, not as head of the Holy See's diplomatic mission to Australia.

Despite working in South America for many years, he never met Pope Francis. ''A papal diplomat obviously has very few opinions about the election of a Pope,'' he said. ''One rejoices that the election has gone well.''

He was surprised by the speed of the decision and had not expected a successful vote until at least the third day of the conclave.

''I think we are going to see him fulfil his ministry as very much his own man, in his own way, and I think he is going to give us his best in every way,'' the nuncio said.

''I sort of know people who know him and I worked for a number of years in Uruguay, which is just across the River Platte from Argentina, and I visited Buenos Aires several times. But that was in the years before Pope Francis was even a bishop.''

The new Pope represents a genuine change that will be felt right across the Christian communion.

''I think he is going to be a great challenge to the church universal,'' he said. ''I think he is going to be a challenge to the church institutions in Rome, but I think it is going to be a very positive challenge and I think it is something that we needed.''

The archbishop, himself a simple man who values ''ordinariness'', is the product of a working class family from the same part of Liverpool that threw up the Beatles.

''I am about 10 years younger than them,'' the 58-year-old said. ''My school was near Strawberry Fields and when it rained I changed buses in Penny Lane.''

He has spent much of his working life as a diplomat in developing countries in Africa and South America, and believes Pope Francis' election as the first ''Second World Pope'' is very significant.

''I think it [his different life experience to other popes] is a positive; it is important that we see the diversity of the Catholic Church, that we see the diversity that exists within the priesthood.''

Archbishop Gallagher is the Vatican's 15th apostolic nuncio to Australia and takes over from Archbishop Giuseppe Lazzarotto, who was appointed nuncio to Israel and apostolic delegate to Jerusalem and Palestine last August.

Archbishop Gallagher was previously the nuncio to Guatemala.