Pope Francis may signal on his visit to Dublin next month that he is considering a separate visit to Northern Ireland, according to a former British Ambassador to the Vatican.
Francis Campbell, who helped to organise Pope Benedict's trip to the UK in 2010, said a papal visit to Northern Ireland could happen in 2019.
The Pope is due visit to Ireland in August.
There are no plans for him to travel across the border.
Mr Campbell said: "With Pope Francis, I would never rule out the spontaneous. Much to the regret of a diplomat, he is a Pope who is very difficult to predict.
"However I think that on this occasion, I think it will be a visit that will be confined to the south and the World Meeting of Families.
"But I think, I would be hopeful, that perhaps there will be some words in the context of his visit that might signal a very strong desire or willingness on the part of Pope Francis to visit Northern Ireland at some point in the very near future.
"Remember we are dealing with someone who is quite advanced in age.
"I think if Pope Francis wishes to come north of the border and wishes to do a visit to Northern Ireland, then one has to think in terms of a timescale of 12 or 18 months."
Pope Francis is 81 years old. The last pontiff to visit the Republic of Ireland was Pope John Paul II.
He drew crowds of over 2.5m - more than half the state's population - in 1979.
Mr Campbell, who is vice chancellor at St Mary's University, London, said Pope Francis' visit is likely to be very different.
"He knows the country somewhat, but on another level he's coming from Latin America, he is not a European like his predecessor, so in a sense this is a visit that is very difficult to type-cast," he said.
Mr Campbell said also it is "inevitable" that Pope Francis will address the issue of sex abuse scandals in the Irish Catholic church.
"It will be an opportunity for Pope Francis to say something directly, not only to the people who identity as Catholic but to the whole of society about the abuse issue and, I hope, to actually be able to give some healing in relation to that as well."
'Refugees and migrants'
Mr Campbell said the Vatican will be choosing their words carefully during the two-day visit.
"How do you tackle the negative aspects, for example, that have been thrown up by the abuse but how do you also remind a society of the deeper meaning in life, that it's not simply about economic wealth?
"That's what I'll be listening for when Pope Francis comes.
"Pope Francis is someone who is critiquing society, in particular western society, reminding western society about those that are marginalised and forgotten.
"People who are homeless, people without health care. Refugees and migrants coming in.
"And I think there will be some challenge or some call, perhaps, to wider Irish society not just to focus on the material, but to focus on something of the soul of the nation, and asking people difficult questions."
Ireland since 1979
Mr Campbell said the Vatican would also be looking at the "huge social change" that has taken place in Ireland.
"And the question is - where does faith and where does the Church and where does society find an accommodation around that?
"These are fundamental questions and they're not the same questions that would have occurred in 1979," he said.