The man credited with brokering the Good Friday agreement has warned that Brexit may threaten “the prospect of peace co-operation” in Northern Ireland.

Former US Senator George Mitchell said he hoped the UK’s decision to leave the European Union would not stop the establishment of a new power-sharing government in Stormont ahead of the assembly elections on 3 March.

He told Sky News: “I believe that the European Union was an important factor that led the United Kingdom and Ireland to co-operate in establishing a process that led to the Good Friday Agreement and I think the UK being out of the European Union may reduce the prospect for further co-operation.”

Secretary of State James Brokenshire called new elections last month after republican party Sinn Fein pulled out of the power-sharing government following a financial scandal involving DUP First Minister Arlene Foster.

The party’s long-standing Deputy First Minister, Martin McGuinness, also stood down due to poor health last month.

Many in Northern Ireland, which voted Remain, are worried about a possible return to border controls between it and the Republic of Ireland as the UK is likely to opt for hard Brexit – which could lead to an increase in violence and instability.

Last month, Stormont’s leaders were given a fresh blow when the Supreme Court ruled the UK Government did not have to get the approval of the country's regional parliaments to trigger Article 50.

Supreme Court Brexit Challenge Show all 13 1 /13 Supreme Court Brexit Challenge Supreme Court Brexit Challenge People wait to enter the public gallery outside the Supreme Court ahead of the challenge against a court ruling that Theresa May's government requires parliamentary approval to start the process of leaving the European Union, in Parliament Square, central London Reuters Supreme Court Brexit Challenge Gina Miller, co-founder of investment fund SCM Private arrives at the Supreme court in London on the first day of a four-day hearing Getty Supreme Court Brexit Challenge A man waves the EU flag in front of the Supreme Court Getty Supreme Court Brexit Challenge Satirical artist Kaya Mar poses with two of his paintings in front of the Supreme Court Getty Supreme Court Brexit Challenge Pro-Europe protestors dressed as Supreme Court Justices stand outside the Supreme Court ahead of the first day of a hearing into whether Parliament's consent is required before the Brexit process can begin. The eleven Supreme Court Justices will hear the government's appeal, following the High Court's recent decision that only Parliament can trigger Article 50 Getty Supreme Court Brexit Challenge The eleven Supreme Court Justices will hear the government's appeal, following the High Court's recent decision that only Parliament can trigger Article 50 Getty Supreme Court Brexit Challenge Businesswoman Gina Miller arrives at the Supreme Court ahead of the first day of a hearing into whether Parliament's consent is required before the Brexit process can begin Getty Supreme Court Brexit Challenge Attorney General Jeremy Wright arrives at the Supreme Court in London EPA Supreme Court Brexit Challenge Protesters outside the Supreme Court in London, where the Government is appealing against a ruling that the Prime Minister must seek MPs' approval to trigger the process of taking Britain out of the European Union PA wire Supreme Court Brexit Challenge A protesters wearing a judge's wigs and robes stands outside the Supreme Court ahead of the challenge against a court ruling that Theresa May's government requires parliamentary approval to start the process of leaving the European Union, in Parliament Square, central London Reuters Supreme Court Brexit Challenge A protester holds up a placard outside the Supreme Court ahead of the challenge against a court ruling that Theresa May's government requires parliamentary approval to start the process of leaving the European Union, in Parliament Square, central London Reuters Supreme Court Brexit Challenge Pro-Europe protestors dressed as Supreme Court Justices stand outside the Supreme Court Getty Supreme Court Brexit Challenge A man waiting to enter the public gallery waves a European Union flag outside the Supreme Court ahead of the challenge against a court ruling that Theresa May's government requires parliamentary approval to start the process of leaving the European Union, in Parliament Square, central London Reuters

The Independent revealed last month that they were planning to block Article 50 if they felt that not enough consideration was being paid to the peace process.

The Good Friday agreement was signed by then UK Prime Minister Tony Blair and then Irish Taoiseach Bernie Ahern in 1998 ending decades of fighting known as the Troubles.