PSNI Chief Constable Sir Hugh Orde tonight warned of the price that will be paid if Rev Ian Paisley and Gerry Adams fail to deliver a deal on future policing arrangements in the province.
He said there was a real danger that if the politicians fail, the political vacuum will be filled by violence during the summer marching season and also by hard-line republican terrorist groups.
As Sinn Féin prepares for a national executive meeting this Saturday to consider moves to support the PSNI, the Chief Constable warned that political brinkmanship over the policing issue could be disastrous.
"If the politicians do not secure a deal this time around, there are substantial implications for policing and substantial implications for the communities who these people are supposed to be representing," he said.
"They need to realise that this is a huge opportunity that could move policing on, that could move confidence in policing on, and create conditions in Northern Ireland that move Northern Ireland on.
"Having now been allowed to officially meet Sinn Féin, my impression is the leadership is committed to joining policing but my impression also is they need to convince a lot of people in their community who are still unsure.
"That is one side of the equation. What is equally important is that other politicians in other parties help to create the space that allows the world to move on.
"Playing brinkmanship is not very clever. They really need to think what the outcomes are of a failure."
The Chief Constable said there was a huge potential for dissident republican activity on the back of another missed opportunity.
"There is a political solution to that," he said. "If it is not sorted out, then it may give dissident republicans a boost to see this collapse and that is really dangerous.
"The failure of legitimate politicians to take responsibility increases their potential to cause damage to this place.
"If you look at the marching season the potential for disorder goes up in a political vacuum. If people this time around are so frustrated that yet again it has failed, we may see this manifested in people expressing dissatisfaction by increasing disorder from what was a very peaceful year last year."
PA