The Home Office has blasted Stormont for failing to support the operation of an FBI-style agency in Northern Ireland to tackle serious organised crime.
Theresa May's office hit out after the Executive on Monday remained deadlocked over the new National Crime Agency (NCA), which will have representation across the rest of the UK as well as in the Republic of Ireland.
The NCA would be involved in helping to target criminals involved in serious crimes like human trafficking, drug smuggling, fuel fraud and cyber crime.
Sinn Fein and the SDLP on Monday blocked a UUP motion calling for the urgent implementation of the NCA in the province, claiming that to do so would create an unaccountable second police force.
Justice Minister David Ford warned that the PSNI does not have the full resources to replicate the work of the NCA.
He also said that there would be "severe" financial cost implications on the PSNI having to tackle serious organised crime alone.
"You are effectively asking the PSNI to tackle organised crime without the full range of tools to do so," he told the Assembly.
The director general of the NCA, Keith Bristow, watched the debate from the public gallery.
He had spent the day, alongside PSNI Assistant Chief Constable Drew Harris, in meetings with the different political parties to explain the role the NCA would be carrying out in Northern Ireland.
On Monday night the Home Office said it was "disappointed by the Executive's decision not to take forward the legislative consent for the new National Crime Agency".
A spokeswoman added that the Home Office remains "committed to delivering a UK-wide crime fighting agency focused on tackling serious, organised and complex crime". She said it is now "looking carefully at the provisions to see how they can best be modified to mitigate operational impact".
It is understood that Mr Ford is concerned that by blocking the NCA from operating in Northern Ireland it will make the sharing of information about criminal conspiracies harder to manage, will prevent the NCA from undertaking civil recovery of assets, and will leave the PSNI having to do extra work without having the resources and expertise in place.
Mr Ford is also concerned that Northern Ireland will be left disadvantaged compared to other police services in the UK.
Although he admitted to the Assembly on Monday that the NCA would not be as accountable as the PSNI, he said he had worked with the Home Office to get a number of safeguards to ensure that the NCA would fit with Northern Ireland policing structures.
The safeguards include: the NCA director general will not have the powers of a constable; he will be required to attend the Policing Board on an annual basis; NCA officers will be subject to the Police Ombudsman; the agency will not be able to direct the PSNI to undertake tasks, and the PSNI will retain primary responsibility for relations with the Garda in respect of Northern Ireland.
However, Sinn Fein and the SDLP said these safeguards were not enough.
"The safeguards are not in statute and therefore what we have here is promises when what we need is law," said SDLP Policing Board member Conall McDevitt.
Sinn Fein Policing Board member Gerry Kelly added: "We are against a second police force not accountable to the Chief Constable. (The NCA) will have more power than the PSNI. Nobody is arguing against the existence of the NCA."
The UUP's Tom Elliott, who brought the motion before the Assembly for consent to give effect to the NCA operating in Northern Ireland, said that people in Northern Ireland have as much right to protection from organised crime as people living in Wales, Scotland, Ireland and England.