"Holidaymakers can now expect to get more for their pounds travelling to one of the Eurozone countries than anywhere else," said Sarah Munro, head of travel money at the Post Office.

Given the continuing concern over the future of the euro, the pound could strengthen further, while reports suggest that hotels and restaurants on the Continent are attempting to attract holidaymakers by reducing prices.

"Our research also shows that prices have plummeted in some of the most popular resorts – especially in Spain and Portugal, where restaurants have slashed their prices," Ms Munro said.

The total average cost of several holiday essentials, including drinks, sun cream and a meal in a local restaurant, has fallen by 42 per cent in the Algarve, for example, and by 40 per cent in Spain, according to the Post Office. Similar research released this week by Thomas Cook also suggested that mainland Spain offers particularly good value for visitors from Britain.

Egypt and Turkey, two destinations that have benefited in recent years from the strength of the euro, may now suffer from a decline in numbers of British visitors, given the current strength of their respective currencies against the pound.

Since last summer, sterling has fallen against the Turkish lira by 10 per cent (2.38 to 2.13) and against the Egyptian pound by 7.5 per cent (8.04 to 7.44). It has also dipped by between 12 to 17 per cent against a host of other currencies, including the East Caribbean dollar (3.90 to 3.45), the South African rand (12.45 to 10.71), the Thai baht (51.11 to 43.48), and the Malaysian ringgit (5.29 to 4.43).

Breaks to North America have also become less cost-effective. The US dollar has risen by 10.5 per cent against the pound since June 2009, and by 26.5 per cent since June 2008. The Canadian dollar has strengthened by 14 per cent since last summer.

"Exchange rates have a huge impact on where Britons choose to travel," said Francis Tuke, a spokeswoman for Abta, the travel association. "The weakening of the euro will undoubtedly encourage us to return to the Eurozone."

She added that hotel prices had fallen in Spain during the past year and that travel companies expected rates to fall in Greece.

Directline Holidays has reported that Greece was the most popular destination for bookings during the second half of May. Maria Whiteman, chief executive, said the company had been able to negotiate cut-price deals for accommodation.

Cheapflights.co.uk, the price-comparison website, has reported that searches for flights to Eurozone destinations increased by 6 per cent during May compared with the same month last year.

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