British investors and homebuyers are rushing to cash in on the plunge in the dollar, which hit a 14-year low of $1.98 against the pound last week and could breach the key $2 mark within days.

The greenback’s decline hit the FTSE 100 index of leading shares because big firms such as Pearson, the publisher, and Carnival, the cruise operator, make most of their sales in America. These will now be worth less when converted into sterling. However, investors have found other ways to profit from the rout.

Spread-betting firms, which let investors gamble on currency movements, said some clients had made hundreds of thousands of pounds since the dollar drubbing started on November 23. Since then, the greenback has shed 3 per cent of its value against sterling and is down 12 per cent over the year.

Simon Denham of Capital Spreads said that in the past two weeks there had been a 50 per cent rise in clients betting on “cable” — the exchange rate between the dollar and the pound — and a 114 per cent jump in people betting on the euro-dollar rate.

He said: “We have a group of four or five investors we call the Cable Group who have made a staggering £150,000 in little over a week by betting the dollar would fall.”

Florida estate agents have also reported a jump in interest from British buyers who think the surge in sterling to its highest level since it was ejected from the European exchange-rate mechanism in 1992 has provided a golden opportunity to snap up a holiday home in the Sunshine State.

A property worth $250,000 would have cost £126,000 on Friday against £145,000 at the start of the year — a saving of £19,000.

Gold is also seeing its biggest inflows of money since the start of the year, according to Barclays Capital, an investment bank. The precious metal is denominated in dollars, so British buyers get more bullion for their pound and have therefore been piling in. Its price in London has gone from a low of $512 earlier this year to $647.

It has not been all good news for British investors. Nearly half of the 100 largest companies in Britain make at least 20 per cent of their sales in the US, and some big UK blue chips, including HSBC, BP and Astra Zeneca, the drugs group, pay dividends in dollars. As a result, investors could find their dividend income is worth about 10 per cent less than last year.

However, some analysts think that now could be one of the best times in decades for British investors to buy into the American market.

Fund managers were already positive about the US on hopes that interest rates had peaked, and the weaker dollar will give American company profits a further boost because it makes exports look better value.

If the pound peaks at about $2, as many analysts expect, British investors could also get a currency boost as the greenback strengthens again.

Ian Kernohan, an economist at Royal London Asset Management, thinks the pound could slip to between $1.85 and $1.90 over the next 12 months. He said: “The fundamentals of the dollar are poor but it needs to fall against the Asian currencies, not sterling.”

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