Europe's heatwave looks set to peak today, but temperatures may remain above normal into the middle of next week, the World Meteorological Organization said, warning that such events could occur with greater frequency in the future.

"The question that everybody is asking looking ahead is -when is this going to end?" said Robert Stefanski, chief of Applied Climate Services at the WMO.

He said: "Unfortunately, looking a tall the models from all our partners at a national and regional level, possibly not until middle of next week."

Britain recorded its highest-ever temperature of 40C (104 degrees Fahrenheit), while firefighters in south western France battled to contain huge forest wildfires as a heatwave rising from the south settled over western Europe.

Mr Stefanski said he expected temperatures to peak today but to stay above average.

At the same briefing, WMO Secretary-General Petteri Taalas warned that he expected to see a "much higher" number of heatwaves in future due to climate change.

"The direction is clear and in the future these kind of heatwaves are going to be normal and we will see even stronger extremes," said Mr Taalas, wearing short sleeves and a red and blue tie, which he said he chose to illustrate the warming trend.

Officials at the same press briefing said they expected more deaths among the elderly and those with pre-existing health conditions due to the ongoing heat wave, as well as challenges for health systems due to increased demand.

A plane intervenes after a wildfire broke out in the village of Tabara, Zamora region, Spain

Firefighters are battling heatwave-related blazes across southern Europe.

There are some signs that conditions were starting to ease after days of blistering highs that have caused hundreds of deaths and left the countryside dangerously dry, authorities said.

However, the heatwave was moving north. Belgium and Germany are expecting the heatwave to hit them in coming days.

Wildfires raged across Portugal, Spain and France and authorities are warning that there is a risk of more, as tinder-dry conditions persisted.

Spain is facing the last day of a more than week-long heatwave, which has caused more than 510 heat-related deaths, according to estimates from the Carlos III Health Institute.

A wildfire raced across a field and engulfed an excavator near the northern town of Tabara, forcing the driver to run for his life as flames burned the clothes off his back.

Locals said the driver of the excavator had been trying to dig a trench between the fire and buildings.

Firefighters try to control a forest fire near Louchats in southwestern France

But orange flames surrounded the vehicle. TV footage showed him emerging from the blaze, tripping, then scrambling to his feet as people shouted out to him and a firefighter ran up to help.

The driver was airlifted to hospital with burns, witnesses said, though there were no detailed reports on his condition.

In El Pont de Vilomara in Catalonia, evacuees gathered outside a civic centre, among them Onofre Munoz, aged 69, who said that his home and van had been completely destroyed.

"We bought the van when I retired and now it's totally scorched. We have nothing," he said.

In Portugal, temperatures dropped over the weekend, but the risk of wildfires remained very high, the Portuguese Institute of Meteorology said.

Around 1,000 firefighters, backed by 284 vehicles and 18 aircraft, were battling ten wildfires, mainly in northern regions, authorities said.

The EU sent a firefighting plane to Slovenia over the weekend, adding to recent deployments to France and Portugal.

"We continue of course to monitor the situation during this unprecedented heatwave and will continue to mobilise support as needed," spokesperson Balazs Ujvari told a briefing.

Half the municipality of Murca was on fire and the bodies of an elderly couple trying to flee had been found inside a "completely charred vehicle," the mayor told local broadcaster SIC.

The EU is in talks with manufacturers to buy more firefighting planes, the EU head of crisis management said.

In the Gironde region in southwestern France, fires have destroyed 14,800 hectares, local authorities said.

More than 14,000 people have been evacuated from the area. France has issued red alerts, the highest possible, for several regions, with residents urged "to be extremely vigilant".

In Italy, where smaller fires have blazed, forecasters expect temperatures above 40C in several regions in coming days.

Switzerland also suffered the effects of the heatwave. Axpo, the operator of the Beznau nuclear plant, said yesterday that it was forced to reduce output so that it does not overheat the Aare river from which it draws its cooling water.