Policing and justice powers must be devolved to the Northern Ireland Assembly before Christmas, it was claimed.

Alex Attwood of the nationalist SDLP called for justice and policing powers to be devolved by December 7, the last day of business before the holiday recess.

The Democratic Unionist Party (DUP) and Sinn Fein are involved in negotiations to seal a deal on transferring powers from London to Belfast.

Mr Attwood said: "The purpose of this amendment is to create certainty, avoid further delay and doubt and to empower the Assembly to do that which it should always have been doing in respect of justice and policing obligations."

He accused Sinn Fein, the Democratic Unionist Party and Ulster Unionist Party of voting against the amendment during committee business. "No surprise there for unionists but it does reveal a lot about the supposed commitment of Sinn Fein to devolution and is in stark contrast to recent Sinn Fein statements that devolution should happen by Christmas," he added.

The Assembly is at the consideration stage of the Department of Justice Bill at Stormont. Ulster Unionist Newry and Armagh MLA Danny Kennedy said they needed clarity over whether this was a meaningful debate or an abstract discussion over constitutional niceties not likely to be faced any time soon.

Sinn Fein South Belfast MLA Alex Maskey said the devolution of policing and justice was a matter for the largest parties in the Assembly. "Sinn Fein and indeed others are working to get the timeframe resolved and no amendment or any proposal here today will compel nor can it compel any party if it has not already agreed to the transfer, particularly if they are the largest parties in the various designations," he said. "This amendment will be meaningless."

The Alliance Party is favourite to produce a justice minister when powers are transferred. The SDLP had argued that it would be entitled to the position according to the process for dividing posts. DUP Strangford MLA Simon Hamilton accused the SDLP of being wedded to the current D'Hondt method of dividing ministries.

He said whoever was selected must be capable of commanding support from both sides of the community. "It is the loss of the chance to have the department of justice in the hands of the SDLP that's at the core of everything... it isn't some high point of principle," he added.