Parts of East Anglia are officially in a state of drought, according to the English environment department Defra and the Environment Agency.

Areas in the south-west, south-east, the Midlands and Wales are experiencing near-drought conditions following the driest spring on record in south-east and central southern England. Overall, England and Wales are at their driest since 1990.

Widespread hosepipe bans are unlikely, although Severn Trent Water has said it is considering "every option". Farmers face restrictions on drawing water from water courses and rivers to protect wildlife.

Farmers' leaders have appealed for authorities not to "just turn taps right off" and instead allow them to eke out supplies. They are attending a "drought summit" on Friday convened by the environment secretary, Caroline Spelman, which will include utility companies, supermarkets and industrial leaders.

In East Anglia some farmers and growers have volunteered to irrigate only at night in an effort to reduce evaporation. Users are forming water co-operatives to share the limited amounts available.

Spelman said: "Water companies are confident that supplies are high enough so that widespread restrictions to the public are unlikely. We're doing all we can to reduce the impact on agriculture and wildlife, but everyone can play their part.

"Households know how to use less water and everyone can do their bit to use water more wisely, not only through the summer but throughout the year."

She told the BBC that water companies were better prepared for the problems than in the past, having drastically cut leaks from pipes. "Just bringing in blanket bans can have unintended consequences. You can, for example, put a garden centre out of business."

Thames Water said its reservoirs were 90% full but urged customers to be careful in their water use as it was too early to predict what the summer would be like.

Paul Leinster, the chief executive of the Environment Agency, said it had worked with water companies and other water users to have plans in place to cope with drought and ensure there was enough water for people, businesses and the environment.

"Many rivers have low flows as result of the dry weather which can harm wildlife and increase the impact of pollution incidents, so we are stepping up our monitoring to be able to respond quickly.

"Low river flows also impact on business, as it abstracts millions of gallons from rivers on a daily basis and we need to ensure this is sustainable."

Craig Bennett, the policy director of Friends of the Earth, told the BBC that although many water companies had "raised their game" on preserving supplies, successive governments had taken "precious little action" to stop "unsustainable abstractions" and limit building where there was not sufficient water infrastructure.