Under the ban, which Southern Water has imposed from Friday, hosepipes cannot be used to water gardens and clean cars, and ornamental ponds and swimming pools must not be filled.

The restriction is the first to be put in place in the region since 2012.

The officially-named Temporary Use Ban also prohibits the filling of paddling pools and the cleaning of walls, windows, paths and patios.

South East Water has also announced a ban for its customers in Kent and Sussex from 12 August.

Parts of England have seen the driest July in records dating back to 1836, following the driest eight-month period from November 2021 for the country since 1976.

It also comes as the Met Office has warned there is "very little meaningful rain" on the horizon for parched areas of England as temperatures are set to climb into the 30s next week.

Find out the weather forecast for your area

Other firms have so far held off bringing in restrictions despite low water levels, though some say they may need to implement bans if the dry weather continues.

Householders who have not yet been hit by restrictions are being urged to avoid using hosepipes for watering the garden or cleaning the car.

Southern Water stressed there was no risk to the overall water supply, but the ban was needed to protect the environment during one of the driest years on record, accompanied by record temperatures.

"We haven't taken this decision lightly, and we know the temporary use ban will have an impact on our customers," said Dr Alison Hoyle, director of risk and compliance at Southern Water.

"We're asking everyone in Hampshire and the Isle of Wight to do their bit by supporting these measures and only use the water that they need."

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'Perilous position'

But water companies have been criticised by nature campaigners for leaving it to "the last possible moment" to bring in restrictions, when rivers are in a "desperate" state, and for last-minute announcements that spur an increase in water demand before hosepipe bans come in.

Mark Lloyd, chief executive of The Rivers Trust, said: "Every year we get to this perilous position and at the last possible moment, when the rivers are at their lowest, we get discussion of temporary use bans.

"Announcing it at the last minute causes people to rush to wash their cars and fill their paddling pools, wash the dog, and causes an increase in demand before the ban comes in.

"This should happen before the rivers come to a desperate condition and there's not enough water for wildlife."