Good Friday Agreement: How Blair and Ahern brought new focus

It is 25 years since the signing of the Good Friday Agreement, the peace deal that brought an end to the Troubles. How did the arrival of new leaders in both the UK and Republic of Ireland help bring fresh momentum to the talks?

The impressive King's Hall at Balmoral today operates as a multi-million pound health and well-being centre but the complex in south Belfast has played host to many memorable cultural and sporting events over the years.

For decades, it was home to the annual multi-day Balmoral Show, the biggest agricultural event in Northern Ireland.

Music lovers flocked there to hear the sounds of The Beatles, David Bowie and Bruce Springsteen, among many others, while boxers Barry McGuigan, Wayne McCullough and Chris Eubank have all entertained fight fans.

But the King's Hall's important role in our political history is perhaps less well known.

In May 1998, under the gaze of the world's media, the result of the Good Friday Agreement referendum was revealed at the King's Hall, revealing 71% of voters had backed the deal.

A year earlier it was the venue for a key moment when the faltering peace process was given a boost.

Just days after becoming prime minister, Tony Blair came to the King's Hall complex to try to get political talks back on track.

He delivered a bold plea to republicans, declaring: "My message to Sinn Féin is clear. The settlement train is leaving. I want you on that train but it is leaving anyway and I will not allow it to wait for you.''

Tony Blair won the 1997 general election with a massive parliamentary majority and Northern Ireland was one of his priorities.

Tom Kelly, who would initially work as director of communications with the Northern Ireland Office and then as the prime minister's official spokesperson, said the new leader was determined to get a breakthrough.

"He also said the peace process was something that was a responsibility that weighed not just on the mind but on the soul. It was personal," he added.

New leadership in the UK was soon mirrored in the Republic of Ireland, where Bertie Ahern became taoiseach (Irish prime minister) in June 1997.

Diplomat Dan Mulhall, who worked in the Irish Department of Foreign Affairs and would become directly involved with the signing of the Good Friday Agreement, said the arrival of Blair and Ahern changed the political dynamic.

"The fact that you had two new leaders, heads of government coming into office at roughly the same time, I think, gave the whole thing a boost that turned out to be critical in the end."

Political talks got going in June 1997, with republicans told that unless there was an IRA ceasefire Sinn Féin would be left out in the cold.

Social Democratic and Labour Party leader John Hume, who had been talking to Sinn Féin leader Gerry Adams, continued his behind the scenes discussions and, in July 1997, a second IRA ceasefire was announced.

This cessation of violence changed everything, said Prof Marie Coleman from Queen's University Belfast.

"The new Labour government was not as stringent as Sir Patrick Mayhew [ the former Northern Ireland secretary] had been with decommissioning before those talks," she said.

"But certainly there would have been no negotiations going into the autumn of 1997 if there had not been a ceasefire."

US politician Senator George Mitchell was tasked with bringing the parties together and finding common ground - a process that Mr Mulhall recalls as being painstakingly slow.

"George Mitchell had that endurance, and the patience, to be able to cope with the glacial pace of progress," he said.

By the autumn of 1997, talks were under way but it seemed Tony Blair's much reported "settlement train" was making little headway.

He came to Belfast for discussions but was booed and heckled while on a walkabout at Connswater Shopping Centre in east Belfast, underlining the difficulties the talks faced.

However another landmark moment, Prof Coleman said, came at Christmas, when the prime minister hosted Sinn Féin in Downing Street.

"What we saw in December 1997 would bring back images of Michael Collins leading the [Anglo-Irish] Treaty delegation in to talk to [prime minister] David Lloyd George in that very same building over 70 years previously," she said

"So there was a significant historical resonance there."

The months to come, before the deal got over the line, had many twists and turns - talks broke up in Christmas 1997 without agreement.

Then loyalist paramilitaries withdrew their support and, in January, Northern Ireland Secretary Mo Mowlam went into the Maze prison to try to get them back on board.

The new year also brought a wave of killings, with both loyalist and republican paramilitaries blamed.

This led to the loyalist Ulster Democratic Party group, which was linked to the Ulster Defence Association, to be barred from the talks, and then Sinn Féin being expelled.

The prospects of a political deal in February 1998 looked bleak, as Mr Kelly recalled.

"People expected failure - people did not expect success," he said.

History turned out differently. In May 1998, the King's Hall became the place to watch as political history was made.