On the same day as Asda opens its first Ulster store, the first member of the PSNI to switch forces to the Republic's police on a temporary placement have packed their bags and headed south. At the same time, a Garda is reciprocating by undertaking a placement with the PSNI.

If I read the report right, there are two aspects of the scheme. The ones beginning today were placements, which last up to a year. In these, the officers are still responsible to their own force's cheif constable, and won't exercise police powers in the foreign jurisdiction.

Also beginning soon will be secondments, where PSNI officers will wear the Garda uniform, operate with the same powers as the Garda officers and report to the Garda Commissioner - and vice versa. The secondments can last up to 3 years.