It is "intolerable" no one been jailed in the past 12 years for making illicit fuel in Northern Ireland despite it being used to fund Republican terrorism, the Prime Minister has been told.
William McCrea, the DUP MP for South Antrim, urged David Cameron to fully introduce the National Crime Agency to the province at Prime Minister's Questions, suggesting it appeared "terrorists and gangsters" were immune from prosecution.
The Prime Minister told the Commons he would like to see the agency operating fully but added it needed talks with all parties.
He said: "The people of Northern Ireland welcome the success of the PSNI (Police Service of Northern Ireland), assisted through secret recordings made by the British intelligent services, in bringing seven suspected terrorists - including terrorist godfathers - to court on charges of serious violence and Republican activity.
"However, there is anger that while customs officials close an illicit fuel plant every 10 days in Northern Ireland, the profits bankrolled Republican terrorists for years and cost the economy millions, yet not one person has been jailed in the last 12 years.
"Why are these terrorists and gangsters immune from prosecution? Do you agree this is an intolerable situation and will you intervene to have the immediate full operation of the National Crime Agency in Northern Ireland?"
Mr Cameron replied: "First of all, no one who commits crimes in Northern Ireland should be immune from prosecution and I think you are right to pay tribute to the PSNI who, over the last few years have shown what an extraordinarily capable police force they are.
"The point you make about the National Crime Agency is important, we would like to see the work of the National Crime Agency - which is proving itself in operation after operation not just here in the UK but right around the world - it is proving itself, it should be playing a part in Northern Ireland.
"That's a discussion we need to have with all the parties in Northern Ireland and I hope over time we can get everyone to see the sense of having this important organisation there for Ulster."