Hoses should be banned, the environment minister has urged water companies as temperatures are forecast to reach 28°C in Britain on Sunday, in an unusually dry August.
George Eustice said some companies have already taken “rightful” action to mitigate the effects of the prolonged dry weather, while encouraging others to follow suit.
His comments, the first public intervention by ministers, point to potential restrictions on watering gardens, washing cars or filling swimming pools with garden hoses for millions of people in southern England in the coming days.
It comes as forecasters predict warm weather for most of the UK will continue into next week, when conditions will remain dry and ease with little rain or wind.
Southern Water has already imposed a hose ban on customers in Hampshire and on the Isle of Wight, with the measure following exactly one week later for South East Water customers in Kent and Sussex.
Welsh Water also announced a ban on Pembrokeshire and Carmarthenshire later this month.
Mr Eustice wrote in: The Sunday Telegraph“In line with their drought plans, water utilities across the country have rightly taken action to mitigate the effects of this ongoing dry weather using the tools available.
“I strongly urge others to do the same.”
Meteorologists have urged people to avoid the midday sun and stay in the shade as the dry weather is expected to continue for another seven to 10 days.
Highs of 27C and 28C are expected to hit parts of southern and southeastern England on Sunday, with sunny spells forecast for most of the country throughout the day.
Some rain may fall in the west of Scotland, but forecasters say there will also be areas with clear skies.
Met Office senior meteorologist Greg Dewhurst said: “England and Wales will be dry with sunny spells (on Sunday).
“Northern Ireland and parts of Scotland will be more cloudy with a chance of some patchy rain, mostly in the west of Scotland, but there will be sunny spells in Northern Ireland
“Maximum temperatures tomorrow will be around 27 and possibly 28C in the central, southern and south-east England area.
“It will still be in the sun further north. Even east of Scotland we can see 23C.”
It looks like the dry conditions will clash with the garden hose ban already imposed or announced – and more companies are likely to follow suit after the intervention of the Environment Minister.
“For the next seven to 10 days, it looks like it will remain dry in much of the country,” Dewhurst said.
Mr Dewhurst also urged people to take precautions in hot weather to avoid overheating, including closing curtains and windows during the day.
“As the heat wave develops, stay out of the midday sun, try to stay in the shade if you are outside and it is best to close the curtains during the day and open the curtains and windows at night to let in the cooler air. inside,” he said.
“Drink plenty of water and make sure you stay hydrated.”
He added: “In general, August is a wetter month, so it’s quite unusual to have prolonged dry weather in August.”