Now, Fiona Ryan, commissioner for survivors of institutional childhood abuse, is speaking.

She says they are gathered "to hear words that have been delayed for years, are lifetimes late and in many cases, tragically, are too late".

Image source, bbc

Ms Ryan says Sir Anthony Hart's inquiry happened "due to the victims and survivors themselves who fought to be seen and heard by an officialdom that was largely blind and deaf to the abuse they had suffered, to their anger and to their ongoing pain".

"Made to feel ashamed as children. Shunned as adults. Silence was expected. Survivors, however, were not silent. Instead they began speaking out, telling the truth of what had happened to them in these institutions."

Assembly Speaker Alex Maskey is on his feet, welcoming everyone who is due to speak in the chamber this afternoon, as well as those listening in the gallery.

Fiona Ryan, the commissioner for survivors, is up first. There then will be a minute's silence before Stormont ministers deliver their remarks.

You can watch live via the play button at the top of this page.

A campaigner for survivors, Margaret McGuckin, tells BBC NI's Talkback what the apology means

"I think its the first time I've ever got out of bed singing - singing and happy," she says.

"Nothing's going to be hid under the carpet any more or people holding their hands over their ears and not listening.

"For us to be looking into the eyes of the religious orders and the state and the government - we who thought we were the lowest of the low and made to feel that our whole time in the homes."

Chris Page
BBC News Ireland correspondent

Jimmy Stewart is one of thousands of survivors of institutions for children in Northern Ireland where abuse was widespread.

He was taken to Nazareth Lodge in Belfast when he was eight - a place he describes as a "nightmare".

Jimmy, like many other victims, has been left with the long-lasting trauma of the abuse he experienced as a child.

"You don't have nightmares. You don't have flashbacks. It numbs you. Keeps all that stuff away. Until the point it's going to kill you. Which it nearly did to me."

For Jimmy and many others who went through what he did, today is a momentous day.

Read more here.

Image source, Pacemaker

Set up in 2012 and chaired by retired high court judge Sir Anthony Hart (above), the inquiry aimed to identify "systemic failings by institutions or the state in their duties towards those children in their care".

It studied allegations of abuse in 22 homes and other institutions between 1922 and 1995.

During the inquiry, 246 individuals gave evidence in person and a further 87 statements were read into the record.

Sir Anthony concluded there was widespread abuse and mistreatment of young residents at the institutions under investigation.

The largest number of complaints heard in the inquiry related to four Sisters of Nazareth homes, where nuns had physically and emotionally abused children in their care.

Recommendations in the report included compensation for victims, a memorial and a public apology - which is being delivered today, five years later.

You can read the full report here., external

Image source, Getty Images

It has been a long time coming.

Survivors of abuse, committed over a period spanning decades in state-run and other institutions, have been campaigning for years for justice.

Many have been left traumatised by the physical and mental abuse they suffered. Some have died during the long campaign, without getting justice or hearing an apology.

The long-awaited apology was one of the recommendations made in the report findings of the HIA Inquiry, published in 2017.

But for long periods since, Northern Ireland's political institutions have been in turmoil causing delays to the introduction of redress measures and the official apology.

Read more here.

Image source, Getty Images

After 12.30, five Stormont ministers - one from each party in the NI Executive - will apologise to survivors.

Usually it would be the first and deputy first ministers delivering the apology, but with their resignations in February, the five ministers are doing it instead.

Fiona Ryan, the Commissioner for Victims and Survivors of Historical Institutional Abuse (HIA), is also expected to speak. The role was established after it was recommended in the 2017 abuse inquiry report.

Apologies will also be delivered by representatives from six institutions that ran facilities where abuse took place.

The institutions include: The Sisters of Nazareth, De La Salle, Good Shepherd Sisters, Sisters of St Louis, Irish Church Missions and Barnardo's.

The official apology is expected to finish up at about 1.50pm, after which we will hear reaction from survivors.

Read more here.

Hello and welcome - today we'll be covering the official apology being delivered from Stormont to victims and survivors of historical institutional abuse in Northern Ireland.

The apology was recommended five years ago as part of the findings of a far-reaching inquiry.

It marks a significant moment for campaigners, who for years have lobbied for the state to recognise decades of abuse carried out in institutions across Northern Ireland.

The apology will be delivered in Stormont's Assembly Chamber at 12.30pm, with ministers from each party and a number of representatives from institutions due to speak.

You can watch proceedings live by clicking the play button at the top of the page and follow along with text updates here.