Northern Ireland's unionist leaders are not doing enough to convince their supporters to back the peace process, a senior US official has said.
Mr Richard Haass, the US special envoy for Northern Ireland, said demonstrable progress was being made despite setbacks such as the recent surge in sectarian violence.
But the peace process was being harmed by the failure of unionist leaders to "sell" the benefits of the Belfast Agreement, he said on his return from a visit to Britain and Ireland.
"Amongst unionists, support for the Good Friday Agreement is at something of a low ebb, in part due to events on the ground, but also, I believe, due to a failure of the Unionist leadership to sell the benefits of the GFA, to make the benefits of the GFA clear to their constituents," he told reporters at the State Department in Washington.
Mr Haass hailed reforms of the police in Northern Ireland and said Washington would continue to strongly support the new Police Service of Northern Ireland.
He acknowledged that allegations of past RUC abuses and collusion with pro-British paramilitaries were troubling and should be "thoroughly and expeditously" investigated.
At the same time though, he appealed for young Catholics seeking a law enforcement career to join the new force, saying they should be able to do so without fear of intimidation or physical harm.
Mr Haass said confidence in policing was "key" to the demilitarisation of Northern Ireland and urged that the IRA speed up and make more transparent its decommissioning of weapons.