Nationalists must set aside "petty prejudices" and back a new FBI-style anti-crime agency for the safety of people in Northern Ireland, it has been claimed.
As well as replacing the Serious Organised Crime Agency, the National Crime Agency (NCA) incorporates the work of the Child Exploitation and Online Protection Centre, and the national cyber crime unit.
It will target crime gangs operating over local, national and international borders.
But in Northern Ireland its powers have been restricted to non-devolved matters such as immigration – a situation described as disappointing by the deputy director of the NCA.
The NCA assumed its powers yesterday and the 4,000-strong agency has an annual budget of almost half a billion pounds.
However, its reach in Northern Ireland is limited because Sinn Fein and the SDLP blocked a move to give the NCA full powers over fears it could lead to a parallel police force unaccountable to the Northern Ireland Policing Board.
Both parties were last night accused of exposing Northern Ireland to organised criminal gangs due to "petty prejudices". And they were urged to reconsider their stance in regard to the NCA.
"The nationalist parties in effect have told the people of Northern Ireland that they put their constitutional preference ahead of efforts to track down child-sex abusers online and human traffickers," said DUP MLA Jonathan Craig, a Policing Board member.
"There still remains opportunities for these parties to actually put the people of Northern Ireland and their safety above their own party political interests.
"The smokescreen raised about accountability was answered by the NCA some time ago. All we are left with now is not a principled stance but a politically and morally bankrupt competition between nationalist parties."
UUP MEP Jim Nicholson said he had serious concerns about the implications of the NCA not being fully operational in Northern Ireland.
One of the major concerns is the region could now become an attractive location for organised criminals looking to hide their assets or the proceeds of crimes.
But Sinn Fein MLA and Policing Board member Pat Sheehan said nationalists had not been given adequate assurances regarding the accountability of NCA here.
"The National Crime Agency is refusing to be accountable to the normal mechanisms negotiated in the Good Friday Agreement and over the last number of years," he said.
"We recognise the importance of co-operation between different agencies to combat organised crime and this is clearly working on a north/south basis in Ireland and between police in Ireland, Britain and in other police agencies throughout the world.
"I raised this issue with Matt Baggott at the latest Policing Board meeting and asked would there be any blockage to the sharing of information and his very clear answer was 'no'."
SDLP Stormont justice committee member Alban Maginness said the apprehension of nationalists and republicans was not surprising.
"Given our history – the meddling and malign interference of British intelligence agencies in the past, particularly in relation to the RUC – it is little wonder that we have grave reservations."
His party's leader, Alasdair McDonnell, added: "We've got to get that right for all of our citizens and I believe that with good will, with flexibility, then we can work our way through this, but I cannot say to you with hand on heart at this moment in time that we will achieve that."
The NCA's deputy director Phil Gormley said he was disappointed the agency was restricted here.
"We're determined to do all that we can within the limitations placed upon us to better protect the people of Northern Ireland and cut serious and organised crime," he said. "It is a disappointment on a professional level that we don't have the powers and can't operate in quite the same way that we can in the rest of the UK."
The PSNI chief constable, Matt Baggott, recently said lives would be put at risk by hampering the work of the NCA here.
Justice Minister David Ford said efforts to tackle child exploitation, cyber crime, asset recovery and drugs trafficking were severely curtailed because the NCA was not fully operational in the region.
Mr Ford claimed Northern Ireland was now viewed as the UK's poor cousin when it comes to dealing with serious organised crime.
He insisted he has worked hard with the Home Office to secure stringent accountability mechanisms including a guarantee that the NCA would be answerable to the PSNI chief constable.
"The nationalist parties in effect have told the people of Northern Ireland that they put their constitutional preference ahead of efforts to track down child-sex abusers online and human traffickers. There still remains opportunities for these parties to actually put the people of Northern Ireland and their safety above their own party political interests. The smokescreen raised about accountability was clearly answered by the NCA some time ago and all we are left with now is not a principled stance but a politically and morally bankrupt competition between nationalist parties." MLA Jonathan Craig