London - (AFP) - The British government was accused Sunday of not dealing seriously with the heat wave , which is approaching a state of emergency, with climate forecasters warning of a threat to lives.

British Prime Minister Boris Johnson did not attend a cabinet crisis meeting held at the government headquarters on Sunday, preferring to spend the day off at his summer residence in Checkers, where he is scheduled to hold a farewell party for his friends before leaving office in September.

Deputy Prime Minister Dominic Raab welcomed the possibility of the temperature exceeding 40 degrees Celsius in England for the first time.

"Obviously, what we're talking about is commonsense advice (such as) drinking fluids, sheltering from the sun during the hottest times and wearing sunscreen," Raab told Sky News on Sunday.

"We have to enjoy the sunshine and we have to be flexible enough during the pressures that it will cause," he added, insisting that there was no reason to close schools during the extreme temperatures on Monday and Tuesday.

His remarks raised eyebrows, as did Johnson's failure to attend the meeting held at the Prime Minister's Office to discuss the government's response to the heat wave.

Johnson stepped down as leader of the Conservative Party, partly due to his partying during lockdowns imposed to contain the spread of Covid.

Responding to Raab's remarks, Tracy Nichols, executive director of the College of Paramedics, told Sky: "It's not like a warm, fun day when we can put on sunscreen and go out and enjoy a swim and eat lunch outside."

"It is a dangerous heat wave that could later lead to death because it is very severe," she added.

"In this country, we are not prepared for this kind of heat," she added.

In contrast to Raab's calmness, after Saturday's meeting Minister Kate Malthouse warned transport services faced "significant disruptions" during the heatwave and advised working from home if possible.

London is expected to record the highest temperatures, and Mayor Sadiq Khan advised residents not to use public transport except when "absolutely necessary".

The readiness of ambulance services was raised, while schools in the south of England decided not to open their doors.

Police urged residents to stay away from waterways after a 16-year-old boy drowned in a canal in Manchester, northwest England, on Saturday.

Britain's government's meteorological agency issued its highest heat warning, warning of a "risk of death" and attributing the heatwave to human-caused climate change.

The maximum temperature recorded in Britain was 38.7 degrees Celsius in Cambridge, in eastern England, on July 25, 2019. However, the agency expected the temperature to exceed this limit this week.