The Commission's Schengen Borders Code allows EU Member States to temporarily reintroduce border control at the internal borders "in the event of a serious threat to public policy or internal security." However, it notes that this measure must only be applied as a last resort and in exceptional situations. 

France notified the Commission of the reintroduction of border controls with Belgium, Luxembourg, Germany, the Swiss Confederation, Italy, and Spain (land, air, and sea) for six months starting from 1 November 2024. In its explanation, France pointed to "serious threats to public policy, public order, and internal security" posed by, inter alia, "the growing presence of criminal networks facilitating irregular migration and smuggling, and migration flows that risk infiltration by radicalised individuals, as well as the irregular crossings on the Channel and North Sea borders, along with rising violence among migrants, particularly in northern coastal areas...". Checks were first introduced in December 2015 following the Paris terrorist attacks. Since then, France informed the European Commission of nearly 20 extensions related to various security concerns.

The checks are not being carried out systematically, so not everyone who crosses the border is being checked. Still, people crossing the border into France should carry their identification documents on them and be prepared for border guards to perform checks. 

For further information, please view this page and read this press release.