The future of Northern Ireland's power-sharing government are hanging in the balance as the British and Irish premiers committed themselves to lengthy talks to secure a rescue deal.
Prime Minister Gordon Brown and Taoiseach Brian Cowen are set for negotiations through the night between the Democratic Unionists and Sinn Fein at Hillsborough Castle, Co Down, aimed at resolving the crisis over the stalled devolution of law and order powers to the region.
The two leaders are understood to have cleared their diaries for the coming days in anticipation of intensive exchanges with the rival politicians.
They jetted into the region earlier on Monday after a last-ditch attempt by Sinn Fein and the DUP to find agreement failed.
Their dramatic intervention came amid fears republicans could collapse the fragile institutions - forcing a snap assembly election - if the DUP does not agree to a swift transfer of the powers from Westminster.
While Sinn Fein said late on Monday that they are still holding out for a firm devolution date, the DUP again insisted they require concessions on how loyal order parades are managed before they give the go ahead for the transfer.
Northern Ireland's largest unionist party did, however, indicate they would be open to proposals on how to resolve the thorny parades issue.