Deputy First Minister Martin McGuinness has accused unionists of “dancing to the tune” of extremists.
Mr McGuinness made the comment after the leaders of the five main parties met at Stormont to discuss the proposals put forward by US diplomat Dr Richard Haass on dealing with flags, parading and the past.
Sinn Féin and the SDLP backed the Haass proposals but the two main unionist parties, together with Alliance, rejected the plans.
The senior Sinn Féin leader said both the DUP and UUP have allowed the views of extremists to dictate their response to the Haass talks process.
“I have watched over the course of the last 18 months unionist parties dancing to the tune of extremists within their own community and that has to end.
“I say that because I believe the influence of these people has impacted on the Haass negotiations and the Haass outcome.
“This is a time for leadership, this is a time for standing up to extremists who are trying to bring this process down,” he said.
Mr McGuinness said he had faced down extremists within his own community despite attacks on his family and home.