LONDON – Britain’s exit from the European Union is not likely to hurt international co-operation against crime and terrorism, London’s police chief said Wednesday.

Metropolitan Police Commissioner Bernard Hogan-Howe said he expects Brexit to be “net neutral.”

Hogan-Howe told journalists that Britain should be able to retain some form of association with the EU police organization, Europol, and “maintain similar arrangements” to the current European Arrest Warrant, which allows for quick arrest and extradition of suspects across the bloc.

“There is a joint benefit for all of us in maintaining that arrangement,” he said. “If somebody stabs someone in London and disappears to Paris, the French don’t want them, and we want them back.

“We will continue to work together. Just getting the arrangements in place will take some kind of effort,” he said.

Hogan-Howe, who is stepping down next month after 5 1/2 years, said cross-border co-operation was essential to deal with the potential threat posed by an estimated 12,000 people who travelled from Europe to areas of Syria controlled by the Islamic State group.

About half have returned to Europe, and more are expected to do so as the territory controlled by IS shrinks.

Hogan-Howe said they would return “militarized, brutalized” and with militant contacts, and “all of Europe will have to consider how we deal with that threat.”

British police adapted their tactics to the evolving terrorist threat after deadly truck attacks in Nice and Berlin last year, he said.

But, he said, “I can’t guarantee that that type of attack is impossible here.”

Britain’s threat level from international terrorism stands at “severe,” the second-highest rung on a 5-point scale, meaning an attack is highly likely.