Firefighters in France hold back vast wildfire as heat returns to test their grip

Firefighters prevented a vast wildfire in south-west France from spreading overnight into Tuesday, bringing several flare-ups near Atlantic coast dunes under control, although rising temperatures and drier conditions are expected to test containment efforts.

The fire remained stabilised as of 6am on Tuesday after a relatively calm night, with the burned area unchanged at 420 square kilometres, the Gironde prefecture said.

Authorities said several flare-ups were detected overnight north of Le Porge and in dune areas north of Cap Ferret, but firefighters quickly brought them under control.

The affected areas lie along the Atlantic coast west of Bordeaux, where emergency crews have been battling the blaze since it broke out near Saumos last week.

The wildfire has proved highly unpredictable, at times developing into a self-sustaining firestorm. It has burned an area four times the size of Paris and forced around 220,000 people to evacuate.

Although the fire's advance has been halted, officials warned that smouldering vegetation and falling humidity could still trigger fresh outbreaks.

Firefighters and military engineers resumed work early on Tuesday to strengthen tactical firebreaks aimed at preventing the flames from spreading further. Authorities said 103 kilometres of firebreaks have been created.

A total of 93 firefighters have been injured during the operation, according to the prefecture.

Part of the A63 motorway remained closed, while rail services south of Bordeaux continued to be suspended, except on the route to Toulouse.

Thousands return home

The situation in Gironde improved as thousands of residents and holidaymakers began returning home following a separate wildfire in the neighbouring Landes region that displaced more than 30,000 people.

French President Emmanuel Macron said on Monday evening that the Landes wildfire had been contained, while regional authorities described it as "fixed", meaning its spread had been halted and no new outbreaks had been detected.

Around 15,000 people were allowed to return from Monday night to Sanguinet, Parentis-en-Born and parts of Biscarrosse.

Residents of Biscarrosse's aviation district and a large campsite were also permitted to return, although several neighbourhoods remained off limits.

The return marked a significant step towards recovery for communities evacuated during the height of the summer holiday season as flames swept through forests and tourist areas. Roads linking Biscarrosse, Parentis-en-Born and Sanguinet have also reopened for residents and essential travel.

Authorities cautioned that the Landes fire had not yet been fully extinguished. Hot spots, strong winds and prolonged drought could still cause flare-ups, and monitoring and extinguishing operations are expected to continue for days, or possibly weeks.

The improving situation faces another challenge as temperatures are forecast to rise again on Tuesday.

France's national weather service placed Gironde under a yellow heat warning from midday, with inland temperatures expected to reach between 33 and 35 degrees Celsius.

South-easterly winds are forecast across the department, while westerly sea breezes are expected along the coast.

Successive heatwaves have left forests and scrubland exceptionally dry, fuelling wildfires across France and other parts of southern Europe.