France is trying to contain coronavirus surges with tighter lockdown orders in Dunkirk and along its border with Germany.
Conditions for cross-border workers are being tightened and they will need to provide proof of negative Covid tests if they try to visit Germany for non-work reasons.
In Dunkirk, the more contagious mutation first discovered in England is gaining ground and the weekend lockdown will mean that all but essential travel is banned.
Emergency vaccine supplies will be shipped to Dunkirk in northern France and the Moselle region, on the German border in eastern France, where cases of the South African variant have been identified.
“The situation is alarming,” health minister Olivier Veran said in Dunkirk. “We’ll take responsible action everywhere it’s needed.”
In Dunkirk and the Hauts-de-Flandre region, which have about 250,000 inhabitants, the weekend lockdowns will mean most people are allowed to leave home only for food shopping and medical appointments.
Large shopping centres will be reduced to offering click and collect services, face masks will be compulsory in cities, and the number of customers allowed in small shops will be cut to one per 15 metres.
"We will reinforce our testing policy to detect, isolate and treat sick people during the entire duration," Mr Veran said.
"As we did in Nice, we will increase the number of vaccines delivered to better protect the most vulnerable people in this region ... there will be 16,700 additional doses of vaccine which will reinforce the vaccination campaign in the region, so 8,200 doses of the Pfizer vaccine and 8,500 doses of the AstraZeneca vaccine.
"It will be part redeployment of vaccines within the region and part an additional national delivery."
The Alpes-Maritimes region in the south, which includes Nice, was earlier ordered into weekend lockdowns, and the Paris region is under scrutiny as case numbers continue to rise there.
France recorded an average of about 20,000 new cases a day since December, and intensive care occupancy recently showed a slight rise, to 67 per cent.
The country has so far ruled out another economy-bashing national lockdown but is also dealing with the EU's comparatively slow distribution of vaccinations.
The EU was criticised for taking almost a month longer than Britain to approve the first vaccines.
