Cooler temperatures have helped firefighters stabilise a wildfire in north-western Spain that reports say is the biggest on record in the country.

The fire in the Sierra de Culebra mountain range in Zamora province has burnt 31,000 hectares (77,000 acres) so far.

The state news agency Efe said that made it the biggest on record since a fire in south-western Huelva province razed just under 30,000 hectares in 2004.

Firefighters eat watermelon during a break in San Martin de Unx in northern Spain
Firefighters eat watermelon during a break in San Martin de Unx in northern Spain (Miguel Oses/AP)

While the Zamora fire was not under complete control, there are no longer flames and it is no longer spreading, authorities said.

A drop in soaring temperatures allowed for about 650 firefighters supported by water-dumping aircraft to establish a perimeter around the fire that started on Wednesday.

People from 18 villages had to be evacuated over the past week.

Elsewhere, 900 people were evacuated from 13 villages in the northern region of Navarra where two wildfires were still active.

Spain has been on alert for an outbreak of intense wildfires as the country last week experienced record temperatures in many places for June.

Experts link the abnormally hot period for Europe to climate change.

A cloud of smoke from the forest fire near Treuenbrietzen can be seen for miles across Lake Seddin, Germany
A cloud of smoke from the forest fire near Treuenbrietzen can be seen for miles across Lake Seddin, Germany (Stephanie Pilick/dpa via AP)

In Germany, heavy showers overnight and on Monday helped largely extinguish two big forest fires about 20 kilometres (12-and-a-half miles) apart to the south-west of Berlin.

Officials said hundreds of people were able to return to their homes after being evacuated as a precaution over the weekend.

Roads were also reopened.

Hundreds of firefighters remained on the scene amid fears that wind could reignite smouldering embers.