Sinn Fein and the DUP are at loggerheads over policing and justice
Policing and justice powers in Northern Ireland may not be devolved for years, the DUP's Gregory Campbell has said.
The East Londonderry MP said there was no prospect of a date for devolution being given before Christmas.
At the weekend, Sinn Fein's Martin McGuinness said a date must be set by then and the powers transferred early in 2010.
The issue is set to be discussed when Prime Minister Gordon Brown meets his Irish counterpart Brian Cowen later.
The DUP and Sinn Fein have been arguing for months about policing and justice, often referred to as the "last piece of the devolution jigsaw".
Speaking on Monday, Mr Campbell said: "It will take years, for not only my colleagues and myself, but for many in the unionist community to see Sinn Fein continuing to work the Northern Ireland Assembly and not using it as some sort of battering ram, because that's where we are now.
"It appears we're moving into the position where their speeches - and Martin McGuinness again and Brian Cowen before him were indicating if policing and justice doesn't happen and there's no date by Christmas then we're in for this train wreck.
"Well if that's the case let them spell it out."
Speaking at a republican event at the weekend Sinn Fein national chairperson Declan Kearney said the DUP had to "make its mind up now".
Gregory Campbell said a date for devolution would not be set soon
"In recent weeks all the evidence indicates the DUP have no intention to support the transfer of policing and justice powers," he said.
"Absolutely nothing suggests this position will change. Their continued intransigence is a serious political mistake. It is a train-wreck political strategy and political consequences will be inevitable."
Mr McGuinness, who is NI's deputy first minister, met Taoiseach Cowen over the weekend and said that "ongoing attacks" by DUP First Minister Peter Robinson on the decision-making processes were of concern.
"I see these attacks as a very clear example of the failure on the part of the DUP to embrace the equality, partnership and power-sharing arrangements which lie at the heart of these agreements," he said.
Mr Robinson has said that he wants community designation at the assembly replaced by a 65% weighted majority system to "ensure widespread support" but which would stop any single party having "a veto on progress".
"It would encourage co-operation and compromise and end the potential of blackmail by stalemate," he told a DUP meeting in Foyle last week.
He said that much had been achieved by the Executive, but the "areas of disagreement" undermined the administration's credibility.
"The continual inability to agree on a range of issues drains credibility from the operation of devolution and if it continues over a long period of time will undoubtedly threaten its long-term survival," he said.
"I do not believe that this is in anyone's best interests."