After just five days in circulation, the European single currency is already taking over.

More than half of all cash transactions are now being conducted in euros, the European Commission has said.

Latest figures show that the single currency is being used in about 55% of all cash payments in the 12 member states.

And 99% of cash machines have been converted to the single currency.

But the use of the euro varies from country to country.

In Greece and the Netherlands, more than 80% of transactions are being completed in euros.

In Germany, Austria, Finland, Portugal and Ireland the money is being used in well over half of all transactions, while in the rest of the euro zone, at least a quarter of all deals are in euros.

Euro shortage

Every time an old currency is spent it should be removed from circulation and the change given in euros.

Consumers have been urged to change their old money for euros

But this is creating a problem for shopkeepers.

It had been expected that most people would change their money at a bank, but many people are just spending it instead.

This is helping to speed up the distribution of the euro, but it is also causing a shortage of small denomination euro notes in shops.

The Netherlands is one of the countries having to cope with a shortage of the new currency - even having to manufacture more euros to cope with demand.

In some cases, businesses are giving change in guilders, but others say they ask the customer to pay with a bank card instead, or just forget about the difference if it is just a few cents.

Banks blamed

Holland's Small and Medium Size Business Association has blamed the banks for loading the cash machines with large denomination notes, saying there was a severe shortage of five, 10 and 20 euro notes.

Shops have been running out of small denominations

The Dutch Food Retailers Association sounded the alarm on Friday as hundreds of supermarkets were affected by the shortage of euros.

The Euro Forum says the situation is under control and that most Dutch people now have smaller euro notes in their wallets after extra deliveries of cash from the Dutch central bank.

The European Commission, for its part, is asking people to change their money at their bank before they go shopping.