Update: 7.15pmPope Francis has said he hopes the World Meeting of Families will bring "renewed encouragement to families everywhere".

In a video message relased ths evening ahead of his visit to Ireland Pope Francis said he is "excited" about his return to Ireland.

He studied in Dublin for three months back in the early 1980s.

Pope Francis will attend a number of events in Dublin and visit Knock Shrine in Co Mayo and will meet victims of clerical sexual abuse during his visit.

The video message coincided with the opening of the major family-themed event in Dublin this evening.

In the video he said: "I hope that this festival will be a source of renewed encouragement to families everywhere, especially those families that will be present in Dublin.

"May it remind us all of the essential place of the family in the life of society and in the building of a better future for today’s young people."

He went on: "Although the specific reason for my visit to Ireland is the World Meeting of Families, I would like to include all the members of the Irish family," said the Pope.

"In a particular way, I pray that it may further the growth of unity and reconciliation among all Christ's followers, as a sign of that lasting peace which is God's dream for our whole human family."

In the opening message, the pontiff went on: "As I prepare to visit Ireland in a few days' time for the World Meeting of Families, I send a warm word of greeting to all the Irish people. I am excited at the thought of returning to Ireland."

Pilgrims arrive for the opening ceremony of the World Meeting of Families at the RDS in Dublin. Picture: Niall Carson/PA Wire

4.30pm: Pope expresses hope World Meeting of Families will bring "encouragement to families everywhere".

Senator Rónán Mullen has criticised former President Mary McAleese’s description of the World Meeting of Families as a ‘right-wing’ rally.

The Senator said it would offend thousands of people who were hoping for the Pope’s visit this weekend to Ireland to be a moment of reconciliation and celebration.

Mr Mullen made his comments as it was revealed that Pope Francis will meet clerical sex abuse victims when he visits Ireland this weekend.

The Pope is due to arrive in Dublin on Saturday for two days of meetings with families and political authorities as well as a trip to Knock.

Earlier this week the Pope condemned the "atrocities" of child sex abuse and clerical cover-ups in a strongly worded letter to members of the church.

Earlier today the Vatican confirmed the Pope would be meeting with abuse survivors.

Senator Mullen said: “Thousands of Irish people, including many returned missionaries, but also ordinary families from parishes around Ireland, are upset by the current negativity towards the Church that they love.

“These are not people who want to hide from uncomfortable truths. They are as disgusted as everyone else by the behaviour of some bishops and cardinals who failed to report child sexual abuse and who were, in some cases, molesters and predators themselves.”

“They are angry at the mocking disregard some of these churchmen have shown for the civil law and for the church’s own moral teachings."

He said that he, and many Irish people within the Church, also believe any bishop or cardinal involved in the cover-up of the scandal should not stay in office.

Mr Mullen said: “This is a time of reform for the Catholic Church. Much progress has been made in Ireland, and perhaps much more needs to be done.

“But the drumbeat of negativity towards the Pope’s visit, and the need that some prominent people feel to chastise the Catholic Church without equally acknowledging the huge force for goodness and love that the Church has been and still is, is disrespectful to thousands of people."

"They had hoped that this weekend’s event would be a moment of truth-telling, but also of reconciliation and celebration. They are upset that some people apparently don’t want the event to be a success.

"They will be saddened, in particular, by the term ‘right-wing rally’ used by our former President, Mary McAleese, to describe this week’s World Meeting of Families."

Ms McAleese had also said Ireland is "long past the point of accepting words of simple sorrow" from the Pope about the scandals and also revealed that she has made a formal canonical complaint to Pope Francis about Cardinal Farrell's banning of her speaking at the Vatican in March of this year.

Senator Mullen said: “That label is both unkind and untrue. It is no way to describe the thousands of grounded and generous people who are coming to celebrate their faith and reflect on what it has to say about their lives as families and their commitment as Christians.

"A quick look at the programme for this event and the profile of the people coming will show that Mary McAleese has got these people badly wrong.”

“If our country is to have a decent future, it cannot be based on the disparagement of those with whom we disagree.

"'Building bridges' used to mean reaching out to people you knew you might never agree with, but finding out what you had in common and learning to get along with, and eventually loving, each other."

"It should still mean that." Senator Mullen concluded.

Meanwhile, it has been revealed that the cost of the Pope's visit to Ireland is expected to be €10m more than expected.

The final bill to the state is expected to be somewhere between €20m and €30m.

Pope Francis will be in the country for less than 36 hours.

Taoiseach Leo Varadkar has defended the increase in spending, saying: "The cost relates entirely to the scale of the event.

"Bear in mind there are over half a million people attending the Mass in Phoenix Park, tens of thousands of people in Croke Park and in Knock lining the streets as well.

"So, we have to bear in mind that this is probably, in terms of participation, the biggest event that's happened in over 40 years, that is why the costs are so high."

Update - 3.16pm: Maeve Lewis, executive director of the One in Four charity for those affected by sexual abuse, said it would have been an insult had the Pope not met survivors while in Ireland.

She said some would very much want to engage while others would avoid him due to a sense of "betrayal".

"If the Pope is in an open, listening mode when he meets the survivors he can learn a lot about the terrible devastation of sex abuse and how people feel let down," she said.

"If he makes any promises to survivors in terms of actions he should follow through on that.

"It would be terribly hurtful if the meeting (produced) no concrete outcome as a result of this."

Maeve Lewis

Kate Walmsley, 62, suffered sex abuse at the hands of a priest.

She said: “If he is the head of the Catholic church then he is the person we need to talk to, to put forward the wrongs all the children have suffered and I am one of them.”

Protesters have arranged a series of rallies coinciding with the pontiff’s visit to highlight what they believe has been the church’s failure to properly address wrongdoing.

Today the World Meeting of #Families begins in Dublin. Let us join in prayer with all the families of the world, especially those in difficulty. @WMOF2018 @LaityFamilyLife — Pope Francis (@Pontifex) August 21, 2018

1.04pm: Pope to meet victims of sexual abuse during Ireland visit

Pope Francis will meet clerical sex abuse victims when he visits Ireland this weekend, the Vatican confirmed.

He is due to arrive in Dublin on Saturday for two days of meetings with families and political authorities as well as a trip to Knock.

Earlier this week the Pope condemned the "atrocities" of child sex abuse and clerical cover-ups in a strongly worded letter to members of the church.

The Catholic Church has been rocked by revelations of wrongdoing by members of the religious orders stretching back decades.

A spokeswoman for the Vatican, when asked about the Pope's meeting with survivors, confirmed it would take place.

Protesters have arranged a series of rallies coinciding with the pontiff's trip to highlight what they believe has been the church's failure to properly address wrongdoing.

Last week a grand jury report outlined seven decades of abuse in Pennsylvania.

The investigation found more than 1,000 children had been abused by 300 priests.

The Pope has apologised after defending a bishop in Chile who was accused of hiding abuses by a priest.

The latest Vatican intervention on the issue comes as Ireland gears up for its first papal visit in 40 years during which at least half a million people are expected to attend a papal mass in Dublin's Phoenix Park.

Several protests by groups campaigning for clerical abuse victims are set to take place during the visit.

- Digital Desk and PA