“We’ve sold about 80 of the England loo seats over the last month, which is about 500 per cent more than usual,” Ms Madeley, 39, said. “Fingers crossed we can go all the way because I think there might be a run on them if that happens.”

Not everyone’s passion for Sven-Göran Eriksson’s men extends as far as the lavatory, but the seats (£25, including post and packaging) are among hundreds of items of England memorabilia, from mini-fridges to inflatable goalposts, that are flying off the shelves as fans prepare for tomorrow’s criticial encounter with Portugal.

With temperatures expected to nudge 30C, by kick-off at 4pm the last of the sausages will be blackening on barbeques beneath the St George’s Cross gazebos; the babies will have had an early dinner wearing their England bibs; and the dogs, in their special “Come on England” T-shirts, will have been ordered out to the garden.

It may not have been pretty, but economists say that England’s progress through the first three weeks of the World Cup has generated up to £900 million for the economy.

Simon Wallace, an economist at the Centre for Economics and Business Research, told The Times that the boon could eventually be £1.4 billion. “Over the next eight days, and assuming England go all the way, my estimate is that there could be another £500 million generated for the economy,” he said.

John Butler, chief UK economist at HSBC bank, said: “I don’t want to chance it by saying what the effect there might be if England went on to win.

“Some sectors would do incredibly well, no doubt associated with people drinking more, eating more and perhaps a boost to consumer confidence. But there could be other sectors that would do less well; people may delay taking holidays or be hungover at work, leading to lower productivity.”

Life is expected to grind to a halt at 4pm tomorrow.

The All England Club said that the 40,000 spectators at Wimbledon would not be able to watch the football on the giant screen on “Henman Hill”, but they will be in the minority.

Providing the one-day international between England and Sri Lanka at Headingley Carnegie has finished, Yorkshire County Cricket Club will show the final minutes of the football on the giant screen.

The BBC is providing seven giant outdoor facilities in

Hull, Leeds, Rotherham, Manchester, Bradford, Southampton and Swansea.

The registrar at Manchester Register Office said that he had not been notified of any cancellations. “We’ve got eight marriages and as far as I’m aware they are all going ahead, though whether they turn up is a different matter,” he said.

Across middle England, festivals, fêtes and garden shows will be interrupted.

The Southampton Garden Festival will bring in a screen. At the RAF Waddington Air Show in Lincolnshire, kick-off will coincide with a fly-past by the Red Arrows.

But although high streets are likely to see a drop-off of up to 20 per cent after 3pm, beauty salons and spas are expecting a bumper Saturday.

Alice Avis, of the Sanctuary Spa in Covent Garden, Central London, said: “We are booked out on Saturday and we’ve got a waiting list. Men have been phoning up over the past few weeks to buy gift vouchers for their partners.”

If England lose, travel agents expect a rush of bookings.

FROM PRIVATE BARBECUES TO THE PUBLIC BAR - OUR CUP RUNNETH OVER

Tomorrow there will be

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