On Good Friday, April 10, 1998, an historic agreement was signed, effectively bringing to a close the worst violence of The Troubles. The multi-party accord was signed by all of the major political organisations and parties in Northern Ireland, with the notable exception of the Democratic Unionist Party (DUP). While largely bringing peace, it also helped create financial foundations which have helped to transform areas and communities in the north. On the 25th anniversary of the signing, we step inside the room with the key signatories and retired senior diplomat, George Fergusson, who tells the story of an historic photograph and the moment the agreement was sealed.

The Good Friday Agreement, 25 years old this week, was a document agreed, but not signed by the parties involved.

Sinn Fein had difficulties with the signing concept but this didn’t seem worth worrying about if they were nonetheless able to endorse it.

As a result, the symbolic photo of the day has often been one of Tony Blair and Bertie Ahern, the Irish Taioseach, signing the linked Agreement between the British and Irish Governments – a vital part of the overall structure, but a less fundamental part of the deal. As a very small cog in the British official ‘Talks Team’, I found myself in the part of the chaos that day that produced that picture.

The last few days of the talks are a blur in my mind. Every now and then I would have to take a message to another delegation, in my case usually to the Irish officials.

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At this stage, the heavy lifting was going on between Tony Blair and his close officials, Jonathan Powell and John Holmes, their Irish counterparts and the party leaders.

Odd requests for advice would come out, giving a glimpse of what the sticking points and obstacles were. The chances of success went up and down regularly, with a couple of nearly theres and imminent collapses each day. And the days were 24 hours long, so that even with long periods of nothing happening, the periods of activity were randomly around the clock, so no one got much sleep, or even made it to bed.

One evening things were enlivened by reports that Dr Paisley was leading a march to try to stop the talks, with the aim of getting through the large iron gates at the foot of the totemic Prince of Wales Avenue that leads up to Stormont’s Parliament Buildings.

News came that they had brought down the gates, narrowly avoiding the police inside. I remember various people suddenly no longer being in the canteen who had been there shortly before – members of the Ulster Democratic Party and Progressive Unionist Party, linked respectively to the UDA and UVF. An Irish colleague said, “It’s good that we’ve got someone going out to protect us but I never expected to be relying on that lot.”

The Herald:

In the middle of the night before Good Friday itself I had reason to go the cluster of rooms, next to Sinn Fein’s, that made the Irish delegation office.

My immediate task done, I accepted a cup of tea and stopped to watch the rolling news coverage. After the most recent burst of optimism, the media were gathering outside, but no news was emerging, and we inside had little idea of what was going on either.

A well-known Irish historian, Tim Pat Coogan, filling in time in a commentator’s chair, said: “There will be anxious discussion going on in the antechamber of the Provisional IRA Army Council.” My nameless Irish colleague said “That’s funny. I thought we here were in the ante-chamber of the Army Council.”

At that point, the real action was within the Ulster Unionist Party.

Read more: How Scotland became a refuge for a boy lost in the Troubles

Of all the players that week, the UUP’s leader, David Trimble, was under the greatest pressure. He had come into the talks with the support of only four of his ten MPs. The young Jeffrey Donaldson, today leader of the DUP, had been his main detailed briefer and support negotiator.

The key compromises lay between David Trimble and the Sinn Fein leadership. The internal processes within the Republican movement were – and remain – opaque. But David Trimble’s had to be played out publicly. To general frustration, though events proved him right, in the evening of Maundy Thursday he broke off from the talks, saying he could go no further without getting clearance from the Ulster Unionist Council, the party’s 800 strong supreme body.

It was called into emergency session and he went off to try to persuade it to let him carry on. Only after a couple of hours and a cautious endorsement from the Council, did the process get back into its normal uncertainty.

My recollection is that early in the morning things looked good. Mid-morning, Jeffrey Donaldson shook us all, David Trimble in particular, by dramatically breaking with his leader’s position, over moral qualms about the early release of Republicans and Loyalists convicted of murder.

The Herald:

This was a concern shared by many unionists and quite a few nationalists, and sometimes too lightly dismissed by the public in Scotland and England.

In my mind, including in retrospect, this was one of the areas in which we dealt in what I called to myself ‘constructive hypocrisy’: a moral compromise which circumstances and events justified, but which was genuinely difficult.

Most or all of the coffee machines ran out at about 10am and took about an hour to resume service. With that, and the Donaldson episode, things looked bad again.

In the early afternoon, after one or two further ups and downs, Alistair Campbell told me to clear a room near the main meeting room on the third floor in case agreement was reached.

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My baby was the relatively obscure British-Irish Agreement between the two Governments, which was to be an annex of the Multi-Party Agreement, which in turn would be an annex of the inter-Governmental one. He wanted it signed quickly to clear the way for the press statements. Both principals were under pressure to get away as soon as possible, if Agreement was reached.

Bertie Ahern, the Taoiseach’s, mother had died earlier in the week: he had already done an extraordinary dash to Dublin to attend her funeral and clearly needed to be back quickly. Tony Blair’s pressure was less fundamental, but still real: he was by now several days late for a long promised family holiday in Spain. (So was I, though not in Spain.)

There was a fear that in the excitement if an Agreement was reached, they might rush off without signing the important annex. With Paul Berman, the very patient Foreign Office lawyer, we found an unoccupied room on the third floor and set it up prettily for a formal signing ceremony, with white sheets of paper covering the scruffy tables.

Suddenly, around 5.00 in the evening, agreement was reached. Everything sped up, and seemed slightly unreal.

The Herald:

Alistair Campbell reappeared, telling me that the top priority was now for Messrs Blair and Ahern to get to the media before everybody else. I’d better find a room near the front door so that they could come back in and sign after addressing the press and before returning to their families.

Paul and I grabbed the precious treaty papers – and the white paper to disguise the tables, and rushed off in search of a suitable room. The best bet turned out to be the Ulster Unionists’ conference room, handily near the front door but, like most of the building by this stage, a mess. We couldn’t do much about the cigarette smell but kicked the empty Tango cans into the corners and covered the tables.

I left Paul under instruction to bar the room from all comers, not least the righteous claim of Ulster Unionists, and went off to join one of my Irish counterparts, David Cooney, just inside the main doors.

Outside, through doors with one-way glass, the Heads of Government were speaking to an enormous scaffold gallery of the world’s press. Inside, David and I were ready to pounce to bring them in when they finished, before they could be tempted to head off to the airport.

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When I heard Bertie Ahern, speaking second, finish his remarks, I shot out to retrieve them, only to hear Tony Blair say “Any questions?” and I returned rapidly. (My U-turn sometimes reappears in documentary clips.)  David and I resumed our guard, now joined by a cleaner with a mop, and then David Trimble, who was next to go before the media, the three of us standing in line.

After the strains – and lack of sleep - of the week and the excitement of the day, David Trimble, whose fuse was never long, suddenly turned on David Cooney and in vehement terms made clear that he thought it was no thanks to the Irish Government that the Agreement had been reached, that they had done everything to make it more difficult, and similar comments.

With this out of his system – unfair to the Irish Government and a particularly unreasonable charge to lay directly on David Cooney – we returned to silence, and the cleaner kept mopping. I felt I needed to do something, but it wasn’t the moment to open up argument with David Trimble. Instead, I found myself doing a slow motion step to the front, turned round to David Cooney shook his hand, and resumed my place; and the silence continued.

When we eventually retrieved our Heads of Government, it belatedly occurred to me that we needed a photographer.

The Herald:

I hastily approached the photographer nearest the building and said he needed to come in to take a picture Tony Blair and Bertie Ahern signing something. Not unreasonably, he said he was too busy, the main party leaders were still to come and he needed to take pictures of them. I said there were plenty of other people doing that, he would be the only person taking the other one, it would be pooled, he’d better come. He followed, very reluctantly, turning out to be from Reuters.

To my relief, Paul, now reinforced by another Irish colleague, Rory Montgomery, had successfully defended ‘our’ room and, as long as the eye focused firmly on the back wall and away from the rubbish and soft drink cans, the covered tables with their green and blue blotters and Treaty papers looked quite convincing. I lent Tony Blair my pen (an £8 Parker which, sadly, I left on a train between Warrington and Liverpool two months later), Rory showed Bertie Ahern where to sign – and the picture was taken.

Over the following days, and for long after, it was one of the main pictures depicting the day. It was used on big hoardings by Fianna Fáil for the referendum in the Republic which endorsed the Agreement. Rory and I were airbrushed to make room for the exhortation to vote “Yes”.

My own day ended with a flight to Birmingham to join my family for an Easter holiday in North Oxfordshire. I had a travel agent’s ticket folder with eight or nine flight reservations scribbled in pencil on the cover, reflecting the various changes of plan as deadline after deadline had come and gone over the previous days.

At Birmingham Airport I went to the station office to buy a ticket to Banbury – and was told wearily that no trains were running, because of the floods. News of the rest of the world, including big floods in the English Midlands, had passed me by. And there were no buses either. My wife’s sister said she would come and get me in the farm Land Rover; and meanwhile I waited in the increasingly deserted terminal building, with nothing to do but watch the screens of news channel, running a continuous loop of the agreement in Belfast and the Midlands floods. By this stage, I had had enough of both. The terminal then closed. When the Land Rover arrived, I was just outside the terminal building door, sitting on a folded copy of the Irish Times, too tired even to feel the hand of history.