THERE are almost 30 “key questions” on security after Brexit, a think-tank claims.

According to a report released today by The UK in a Changing Europe, established procedures on information sharing, prisoner transfer and security co-operation are nearing “another potential Brexit cliff-edge”.

The report also warns that establishing new protocols will be “fiendishly difficult” and that little detail has been released so far.

Professor Anand Menon, director of the think-tank, said: “The UK and the EU have a clear incentive to continue to cooperate over law enforcement and counter-terrorism, given the obvious threats confronting them. Both sides have made it clear that they want a close relationship in this area in future.

“But this is fiendishly complex. When negotiations are likely to involve constitutional issues, disagreements over the role of the European Court of Justice, and trade-offs from both sides, good intentions are not enough. Despite a shared desire to cooperate closely in future, nothing can be taken for granted.”

Earlier this month former Nato general secretary Anders Fogh Rasmussen warned Brexit may harm counter-terrorism measures by disrupting the sharing of information.

Calum Steele, general secretary of the Scottish Police Federation, warned the loss of Europol membership may impair crime fighting in Scotland, including efforts to tackle organised crime gangs that operate across borders.

The new report takes in three “key aspects” of future UK-EU law enforcement cooperation, including data-sharing and access to EU databases, the bloc’s police agency, Europol, and the European Arrest Warrant.

Data-protection issues could mean the UK being denied access to Europol data, the report argues. “Without maintaining its status as a trusted recipient of personal data, the UK is unlikely to retain access to Europol databases, and it might have trouble retaining full involvement in its operational projects. A data-adequacy decision may be required before the agency can fully conclude an operational agreement with the UK.”

It further suggests the UK may “overwhelm” Europol with requests if such a deal is not struck and that extraditions could take years, with the UK “struggling” to remove foreign criminals wanted in connection with offences abroad.

The 27 questions included in the paper cover these areas, with the report suggesting that any Europol deal may prompt objections from the Danish government if this “goes further” than its own arrangement.

Meanwhile, the report – which is informed by interviews with academics, lawyers and sources from Westminster and Brussels – warns negotiations over the European Arrest Warrant “took years” with Norway and Iceland and that achieving a similar deal could still mean some EU nations will not be able to surrender their own nationals to the UK.

Menon said: “There is a danger that, unless the British Government acts quickly to define more clearly what it wants and how it might achieve it, another Brexit cliff-edge – in security – might be on the horizon.”

In September, Home Secretary Amber Rudd announced plans to draw up a new UK-EU treaty to “allow us to maintain and strengthen our current level of cooperation and provide a new legal framework to do this”.

The plan includes pinning down ways to “respond to threats as they evolve” and “maintain crime-fighting capabilities”. She added: “Such a treaty would be in the interest of all parties.”