Where a serious threat to public policy or internal security in a Member State requires immediate action to be taken, the Member State concerned may, on an exceptional basis, immediately reintroduce border control at internal borders, for a limited period of up to ten days.

Where a Member State reintroduces border control at internal borders, it shall at the same time notify the other Member States and the Commission accordingly, and shall supply the information referred to in Article 27(1), including the reasons that justify the use of the procedure set out in this Article. The Commission may consult the other Member States immediately upon receipt of the notification.

If the serious threat to public policy or internal security persists beyond the period provided for in paragraph 1 of this Article, the Member State may decide to prolong the border control at internal borders for renewable periods of up to 20 days. In doing so, the Member State concerned shall take into account the criteria referred to in Article 26, including an updated assessment of the necessity and the proportionality of the measure, and shall take into account any new elements.

In the event of such a prolongation, the provisions of Article 27(4) and (5) shall apply mutatis mutandis, and the consultation shall take place without delay after the decision to prolong has been notified to the Commission and to the Member States.

Without prejudice to Article 25(4), the total period during which border control is reintroduced at internal borders, on the basis of the initial period under paragraph 1 of this Article and any prolongations under paragraph 3 of this Article, shall not exceed two months.

The Commission shall inform the European Parliament without delay of notifications made under this Article.