Emergency services are battling wildfires across swathes of southern Europe amid mass evacuations, as warnings sounded in London after Britain's hottest day that the fight against climate change needed to be stepped up.
A blaze fuelled by gale-force winds raged on Wednesday in mountains north of Athens, forcing hundreds including hospital patients to evacuate, and similar numbers fled in central Italy as gas tanks caught in a forest fire near the Tuscan town of Lucca exploded.
A brutal heatwave settled over southern Europe last week, part of a currently developing global pattern of rising temperatures - widely attributed by scientists and climatologists to human activity - that is forecast to dump searing heat on to much of China into late August.
While the record heat experienced last week around parts of the Mediterranean has eased, mercury readings have begun heading up again in Portugal and Spain and rising in Italy.
Wildfires burned in several areas of Italy and 14 cities, including Rome, Milan and Florence, were due to be put on the country's highest heatwave alert on Thursday, up from nine on Wednesday.
Forecasters there said that temperatures were expected to hit 40C across a swathe of the north and centre this week.
That mark was topped in Britain for the first time on Tuesday, shattering the country's previous temperature record by 1.6C.
The Chief of Science and Technology of Britain's Met Office, Stephen Belcher, said that unless greenhouse gas emissions were reduced, the country might experience similar heatwaves every three years.
London mayor Sadiq Khan, a member of the opposition Labour Party, issued a similar warning.
"The sad reality is this is what the future for London and the UK is likely to look like if we don't take strong action now on the climate crisis," he said.
To the south on the European mainland, major wildfires continued to rage.
In Greece, thick clouds of smoke darkened the sky over Mount Penteli 30 kilometres north of Athens, where close to 500 firefighters, 120 fire engines and 15 water-carrying planes tried to contain a blaze that broke out on Tuesday and continued to burn on several fronts.
Authorities said they evacuated nine settlements. One hospital and the National Observatory of Athens were also evacuated and police helped at least 600 residents out of fire-stricken areas.
Strong winds were forecast to persist until Wednesday afternoon.
In Italy, fire crews in the central region of Tuscany battled a wildfire for a third day near the town of Lucca that had destroyed some 560 hectares of forest, authorities said.
It forced about 500 people to evacuate as the flames raged through the night, reaching some villages and causing some liquefied gas tanks to explode.
In the northeastern Friuli Venezia Giulia region, residents were urged to stay indoors because of heavy smoke from a wildfire that started on Tuesday in the Carso area bordering Croatia and Slovenia.
In France, where firefighters in the southwestern Gironde region have been battling since July 12 to contain huge forest fires, Agriculture Minister Marc Fesneau said more money needed to be invested to tackle such threats.
"We are having to confront a quite exceptional situation," he said, referring to damage caused in Brittany and southern France.
President Emmanuel Macron was due to visit the Gironde region on Wednesday as local authorities said improved weather conditions as France's heatwave moved east were helping the battle to contain the flames.