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LONDON - The River Thames has burst its banks, forcing the evacuation of hundreds of homes in the university city of Oxford in the country's worst floods for 60 years.
About 350,000 people faced two weeks without running water and insurance companies said the bill could soar to 3 billion pounds ($7.7bn).
Farmers say harvests have been badly hit and that farm animals in flood-hit areas could die unless water supplies are restored soon.
Visiting the worst-hit area in Gloucestershire, Prime Minister Gordon Brown pledged more cash for stricken areas and more tankers and bottled water to ensure supplies.
Oxford became the new frontline when rivers feeding into the Thames spilled over into its streets, forcing police to evacuate 250 homes. Aerial pictures showed flood waters not far from some of the city's historic college buildings.
Heavy rain is expected overnight local time and Environment Agency officials warned that the river had not yet peaked.
As the flooding spread along the river, officials said Queen Elizabeth's residence at Windsor Castle was not threatened and no property flooding was expected in London -- although heavy storms could always cause flash flooding.
"There are six severe flood warnings in place. It looks as if we are going to get up to 20 millimetres (0.8 inch) of rain across the board tomorrow," an Environment Agency spokesman said.
The insurance bill for floods in June and July could hit 3 billion pounds, insurers say, sparking fears of price hikes.
Milk shortages hit some areas with flooded roads making collections from dairy farms impossible. The rain brought harvesting of barley and rapeseed to a halt in many regions.
One power substation in Oxford was closed as a precaution, after it was partially flooded at the weekend, but customers have not been cut off because supplies were re-routed. Sandbags were piled up to protect other substations in the area.
Economists say the floods will trim back economic growth and are likely to trigger a short-term spike in food prices, but the overall economy is likely to weather the storm in the long run.
One beneficiary of the bad weather was the airline industry. British Airways said seat bookings for long flights were up as holidaymakers escaped the British summer.
"We need to invest more in preventing floods," Brown told parliament. Less than a month into the job as premier, he said everything had to be looked at from infrastructure and drainage to where utilities were located.
In a stark reference to how 21st century weather had changed, Chancellor Alistair Darling said: "Climate change is not a passing trend.
"It is a reality we must factor into everything we do. If we do not, threats to our everyday life -- like the floods this week -- risk becoming common."
- REUTERS
