Michelle O’Neill said the message from the conference marking the 25th anniversary of the Good Friday Agreement has been one of encouragement and has not been “deliberately antagonistic” towards anyone.

Many of the main speakers at the Queen’s University event in Belfast have spoken of the importance of restoring the devolved institutions, with former US secretary of state Hillary Clinton urging politicians to “move forward with the same spirit of unstoppable grit and resolve” that brought peace in 1998.

Sir Jeffrey Donaldson – leader of the DUP which is currently blocking the operation of the powersharing institutions at Stormont – has said “berating unionists won’t solve the problem”.

Hillary Clinton (Niall Carson/PA)

Sinn Fein’s Stormont leader Ms O’Neill said the message from the conference, and its contributors, has been one of “encouragement”.

Speaking to reporters, she said: “I don’t think it’s been deliberately antagonistic towards anybody. I think it’s been absolutely determined to be positive and to try to encourage the parties to come together.

“There isn’t any other show in town.”

Ms O’Neill said she is a big believer in the adage that there is “far more that unites us than divides us”.

She added: “I think there was a clear message to take from the events of the last number of days and indeed last week with the presidential visit – it has been that the courage and wisdom of those in 1998 needs to be very much to the fore today.”

Ms O’Neill said attention from international investors is a tangible outcome of the talks at the Agreement 25 conference.

Sinn Fein vice president Michelle O’Neill and party leader Mary Lou McDonald (Niall Carson/PA)

“I think tangibles you take away, the international stage is looking at us again, as a place that now has access to both markets, the British market and the EU market, so a good place to come and invest and I think that’s important as a tangible,” she said.

“We also have the attention of the American administration in the form of Joe Kennedy, being appointed as a special envoy.

“This is someone who is very much linking democracy, how that all works, having a fully functional executive with investment.

“So there are real potential and real opportunity and hope for us here in terms of the opportunity for us to achieve additional investment.

She added: “Joe Kennedy tells us frequently there are people who are ready and willing to be here so we have to use this as a moment in time to reflect but also look forward and it’s about the next 25 years. And it is about job creation, it is about making people’s lives better, and I think that’s a real tangible from this GFA anniversary period that we’re in.”

Meanwhile, Ms O’Neill also said mental health services in Northern Ireland are “broken” and more needs to be done to tackle generational trauma from the Troubles.

“We’re reflecting on 25 years of the peace process, and that peace is stable and secure, and we should all be secure in that, but I think there’s no doubt that the impact of conflict is intergenerational, there is a trauma there, and we need to invest in our services and there isn’t enough investment in terms of mental health services on the ground,” she said.

Ms O’Neill said that every person needs to feel the benefits of the Good Friday Agreement.

“Every single citizen who lives here needs to feel the benefit of the peace process. And that isn’t always the reality in life, but that’s our job, we have to keep working on that and trying to make sure we reach every single citizen,” she said.