On 11 May 2017, the Council of the European Union adopted an implementing decision providing for a recommendation to extend temporary border controls in exceptional circumstances. From this date onwards, Austria, Germany, Denmark, Sweden and Norway may prolong internal border controls, in specific locations along the borders, for a maximum period of six months. This decision was made in the context of the migration crisis as a response to the serious threat to public order and internal security following secondary movements of irregular migrants.

Under Article 29 of the Schengen Borders Code, border controls at internal borders may be reintroduced In exceptional circumstances where the overall functioning of the Schengen Area without internal border controls is put at risk as a result of persistent serious deficiencies relating to external border controls and insofar as those circumstances constitute a serious threat to public policy or internal security within the area without internal border controls or within parts thereof. Controls may be introduced for a period of up to six months, and may be prolonged, no more than three times, for a further period of up to six months if the exceptional circumstances persist.

Internal border controls should be carried out proportionately and only where it is considered necessary; they should only be carried out as a last resort and when other alternative measures cannot achieve the same effect. Border controls should also be targeted and limited in scope, frequency, location and time to what is strictly necessary to safeguard internal security resulting from the continued risk of secondary movements of irregular migrants.

Concerned Member States should in any case review each week whether controls are still needed and adjust them to the level of threat.