Sinn Fein, the largest Catholic party and the political wing of the Irish Republican Army (IRA) accused London and Dublin of wanting to exclude it from the talks.
"It's a complete debacle," said Sinn Fein president Gerry Adams, accusing Britain and Ireland of conducting a "retrograde, backward, naive" debate.
The biggest party and the largest Protestant group, the Democratic Unionist Party (DUP) refuses to negotiate directly with Sinn Fein.
Britain's Northern Ireland Secretary, Peter Hain, proposed multi-party talks without Sinn Fein, followed by another round including the republican party but without the DUP.
Mr Adams judged the plan "totally unacceptable" and said London and Dublin wanted to drag Northern Ireland back to the days when his party was systematically excluded from negotiations.
The IRA renounced violence in July 2005 and dismantled its arsenal in September.
After the discussions, Mr Adams telephoned Irish Prime Minister Bertie Ahern to complain while his deputy Martin McGuinness contacted London, Adams' spokesman told AFP.
A new round of negotiations between the Northern Irish parties now seems impossible before the March 8 deadline set by Mr Hain for the parties to agree amendments to new legislation on the suspended Northern Irish Assembly and other issues.
The assembly, set up by the April 1998 peace accords, was suspended in October 2002 due to a breakdown in trust between the Protestant and Catholic parties.