Holidaymakers heading to Greece are being urged to make sure they have sufficient cash in euros to get them through their trip amid fears over a possible "Grexit".
Around two million Britons make tourist trips to Greece every year - but travel and money experts said that visitors should not panic over speculation that Greece could exit the eurozone.
Meanwhile, concerns have also been raised over the potential impact of such an exit on UK savers' pensions and Isas as the shockwaves are felt by the markets. One economist said shares could fall by at least 10% if Greece leaves the euro.
Greece's central bank has warned that the country could face an exit from the euro bloc and even the EU if it fails to reach a deal with bailout creditors by the end of the month.
Bob Atkinson, a travel expert at website MoneySuperMarket.com, said tourists should take steps to ensure they are not left stranded without access to money.
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He said: "If you're going to Greece, our recommendation is to have at least four to five days' worth of euros cash on you for the entire time you are there."
He said holidaymakers should also consider taking a small amount of sterling, and that they should keep their money in small notes in case they have difficulty getting change.
"The important thing is to have a cash flow," he said, adding that travel insurance policies often only cover a small amount of cash and travellers should therefore try to store their money in a hotel safety deposit box.
Holidaymakers who are worried about industrial unrest could also consider making sure that strikes are covered in their travel insurance policy, he said. This would need to have been taken out before a strike is announced.
Bookmaker William Hill has now closed the book on a Grexit happening this year.
Andrew Brown, a spokesman for Post Office Travel Money, said: "UK holidaymakers planning trips to Greece shouldn't panic if the country leaves the eurozone.
"If this happened it would take around 18 months for the Greek drachma to be reintroduced."
He also said that holidaymakers should "take enough cash in euros to see them through their holiday".
A spokeswoman for Atba, which represents travel agents and tour operators, also pointed out that if Greece were to exit the euro, the switch to a new currency would take time.
She said: "Euros would likely be accepted in the interim. Holidaymakers heading out to Greece this summer are advised to take some cash in euros with them as well as other payment methods (credit/debit cards) so that they are covered for all situations.
"We would also advise them, as we would with any destination, to take out travel insurance as soon as they book their holiday to provide protection should they need to cancel.
"We do not anticipate that there will be any need for tour operators to re-book their customers to a different destination. At present we have no indication that holidaymakers will be disrupted however, as with all destination matters, we will continue to monitor the situation and work with our members on any developments."
Fears have also been raised that UK savers could see the value of their pensions and Isas tumble if Greece leaves the euro.
Jonathan Loynes, chief European economist at Capital Economics, said shares could fall by at least 10% if Greece left the euro.
But he said that the impact of this for people in the UK with a long-term investment such as a pension was likely to be "relatively short-lived" as it would be overtaken by other influences such as the health of the economy.