Talks resume after over a year of stalemate and are the result of a public outcry over the death of journalist Lyra McKee during a riot in Derry last month.

“We need agreement and all-party power-sharing institutions back in place,” McDonald said, adding: “The two governments are not spectators or referees in this process, they are co-equal guarantors of the people’s agreements and rights.”

The last DUP/Sinn Féin powersharing coalition collapsed in January 2017 when the late Martin McGuinness (Sinn Féin deputy First Minister) quit amid allegations of DUP corruption in a ‘green energy’ scheme. 

The long-standing impasse at Stormont had lasted months and covered issues like the Irish language, same-sex marriage and the legacy of the conflict. 

A veto mechanism used by the DUP to block political change since 2007, known as a petition of concern, is among the issues the current talks will look at.

Sinn Féin McDonald said actions of the British government, such as their deal with the DUP, Brexit and their refusal to honour their obligations on the legacy issues of the past, had dogged the process since 2017. 

She added she would be raising these issues directly with the British Prime Minister on Monday. But she added: “I believe an agreement can be reached and genuine power-sharing can be established.”

Ms McDonald said her party was ready to “do the business” and added: “The current stalemate is not acceptable and not sustainable, there are outstanding issues that need to be resolved, and we believe they can be resolved.” 

Sinn Féin urged optimism as the process got underway. “We will go into these talks with hope and positivity,” McDonald said and added: “We will also go in with our eyes wide open, because we have been to his place before. Whatever happens, we’re very clear that the current political stalemate cannot continue. It’s simply unacceptable at this stage.”

In a joint statement, the Dublin and London governments said party leaders will meet at least once a week to assess progress, while the process will be reviewed by Taoiseach Leo Varadkar and British Prime Minister Theresa May at the end of the month.