About 1,500 people are evacuated near Dunkirk, as the UK and France vow to tackle illegal migration.
France has dismantled a large migrant camp on its northern coast where increasing numbers of people hoping to reach the UK had settled.
French officers pulled down tents and evacuated up to 1,500 migrants from the site, near Dunkirk, early on Tuesday.
Authorities also say they have arrested 35 suspected people smugglers.
France is in a row with the UK over its handling of rising numbers of migrants trying to cross the English Channel from camps in northern France.
Last Thursday 1,185 people made the often dangerous crossing, a record number that the UK government said was “unacceptable”.
The UK has accused French authorities of not doing enough to control the crossings, and called on them to clamp down on people smuggling.
France meanwhile has accused the UK government of blowing the scale of migration out of proportion for political reasons, and failing to deter people from making the crossing.
The issue has damaged UK-France relations, which were already strained over a number of issues, ranging from fishing rights in the Channel, to a deal with Australia on nuclear submarines.
France’s Interior Minister Gérald Darmanin said on Tuesday morning that the migrant camp in the Dunkirk suburb of Grande-Synthe was being evacuated on his instruction.
French police said that 663 people had already been transported on 23 buses to a shelter.
Mr Darmanin said the new arrests meant France had detained more than 1,300 suspected people smugglers since January.
“These smugglers are criminals who exploit human misery, overseers of illegal immigration,” the minister tweeted.
Videos posted on social media showed scores of police vans at the camp, and people being taken onto coaches.
BFM TV said the number of migrants in the camp had more than tripled in two months, from 400 in early September to about 1,500 people recently.
A French government spokesman told broadcaster France Inter that the camp had been dismantled in order to “shelter” the migrants, “especially as winter approaches”.
But migrant organisation Utopia56 said the evacuation would only “lead to a dispersal and silencing of people, without any real accompanying solution”.
More than 23,000 people have made the crossing from France to the UK by boat so far this year, a sharp rise on the 8,404 recorded in 2020.
The UK government has repeatedly promised to make the route unviable.
In an attempt to do this, the UK government has proposed changes to immigration rules, which are being considered by MPs. If approved, these changes would make it harder for anyone arriving by boat to claim asylum successfully.
But humanitarian groups have criticised the plan, which say they will unfairly punish refugees from the poorest parts of the world.
Mr Darmanin met UK Home Secretary Priti Patel on Monday evening to discuss the migrant issue.
In a tweet, Ms Patel said they had “discussed a range of additional steps to tackle the problem and reiterated the importance of working together to make this deadly route unviable”.
A source close to Mr Darmanin told the BBC the ministers discussed technical solutions to fight against organised crime groups. But the French interior minister said “the only way to prevent 100% of crossings was to reduce the attractiveness of the UK for migrants”, the source said.
Hours before the meeting, Mr Darmanin gave a highly critical assessment of British attacks on France’s handling of the migrant situation. In an interview with CNews (in French), Mr Darmanin accused the UK of “using us as a punch-ball in their domestic politics”.
On Tuesday, one of Mr Darmanin’s aides said there was no link between his conversation with Ms Patel and the clearing of the camp in Grande-Synthe.
The clearance had been “scheduled for this date” prior to the phone call, the aide told AFP news agency.