Last night (16.09.), the European Commission received a notification from the Slovenian authorities informing about their intention to temporarily reintroduce controls at its border with the Republic of Hungary, as of today for an initial period of 10 days.
The temporary reintroduction of border controls between Member States is an exceptional possibility explicitly foreseen in and regulated by the Schengen Borders Code, in case of a serious threat to public policy or internal security. The current situation in Slovenia, prima facie, appears to be a situation covered by the rules.
The measures taken by Slovenia today, like those taken by Germany on 13 September and Austria on 15 September, are provisional in nature. The Extraordinary Council of Interior Ministers of 14 September reconfirmed the need to fully apply the EU asylum and Schengen rules.