A fresh war of words over the bitter impasse on the devolution of policing and justice erupted last night after Sinn Fein accused the DUP of having a “train wreck political strategy” that will spark inevitable consequences.

DUP MP Jeffrey Donaldson accused Sinn Fein of refusing to engage with his party over the contentious devolution of powers after the republican party’s national chairperson Declan Kearney warned the problems go deeper than one issue.

Speaking at a republican commemoration at Dunloy in Co Antrim, Mr Kearney said: “In recent weeks all the evidence indicates the DUP have no intention to support the transfer of policing and justice powers.

“Absolutely nothing suggests this position will change,” he said.

“Their continued intransigence is a serious political mistake. It is a train wreck political strategy and political consequences will be inevitable.

“All of this demonstrates that the impasse over policing and justice is about something deeper than a transfer of powers. It’s about whether political unionism is prepared to co-exist with republicans in equality and partnership.”

Prime Minister Gordon Brown is to meet Taoiseach Brian Cowen in Downing Street today, with both premiers keen to avoid a crisis over policing and justice.

Responding to Mr Kearney’s comments, Mr Donaldson told the Belfast Telegraph: “It’s yet more threatening noises from Sinn Fein with the clear implications that they are prepared to walk away from the political institutions.

“The DUP is continuing to engage with the Government in relation to policing and justice and we have made clear what needs to happen before the transfer of powers can take place.

“The reality is that Sinn Fein are refusing to engage with us to resolve the outstanding issues and it is they who are therefore holding up progress.”

Yesterday’s speech by Declan Kearney was not just about the stalemate at Stormont, and addressed dissident republican organisations and their activities in recent days.

He said the IRA “war” had been fought “to a conclusion”.

“There is no other IRA today,” he said. “Nor is there an armed struggle to be finished. Those who choose to masquerade otherwise should disarm and disband.”

Meanwhile, detectives have revisited the scene of a failed bomb attack outside the headquarters of the Policing Board to appeal for information on Saturday.

The attack has been blamed on dissident republicans.

Senior investigating officer Detective Chief Inspector Debbie McMaster said her team were making a number of inquiries, in particular about two vehicles involved. The bomb partially exploded after a black Mazda broke through a barrier of the complex last Saturday.