The PSNI has put out an appeal for more riot-trained police officers from other parts of the UK in anticipation of potential disruption following Brexit.
The Sun reports an email sent to police forces across the UK has asked for officers with "level 2 public order training" to volunteer to assist the PSNI ahead of Britain leaving the EU in March.
Three training days are scheduled to take place ahead of March 29, the day Britain will leave the EU.
The purpose of the training being provided is to give officers the capabilities to carry out the type of policing operations which are more usual in Northern Ireland.
In a statement a PSNI spokesman said: "PSNI are working closely with other UK policing partners in our planning processes.
“While there is, as yet, no indication that mutual aid will be required, preparations for mutual aid form part of our ongoing planning work.
"Planning around mutual aid is something that happens every year across policing and if required, the provision of mutual aid to police services is provided through the National Police Co-ordination Centre.”
A potential threat created by Britain's exit from the European Union has previously been highlighted by PSNI Chief Constable George Hamilton who has called for additional resources to bolster the police force.
In September, Mr Hamilton told the Sunday Times he did not believe some politicians in Westminster understood the scale of the challenge being presented by Brexit, and there was a view it "is sorted and we don't need to worry about it".
"Actually we're working flat out 24/7 to keep a lid on it," he said.
Last month it was announced £16m would be made available to recruit an additional 308 additional PSNI officers and staff by April 2020, as well as funding to bolster resources.
Reacting to the announcement of the funding, Mr Hamilton said: “The ethos of policing with the community has been central to our planning and I want to reassure the communities we serve that this money will be used to keep people safe, by preventing harm, protecting people and bringing offenders to justice.”