Nicholas Jones BBC Political Correspondent

Many people who have been using the euro while on holiday have changed their mind about UK membership of the eurozone, a survey conducted by Radio 5 Live has revealed.

Pro-European politicians had predicted that they would quickly be won over once they started using the currency.

Using the currency made many accept it

850 British visitors were questioned and after having first-hand experience of the new currency, 70 said they had changed their minds in favour of Britain joining.

And 356 said they had already been in favour of the new currency before they left home.

Less than hoped for

After using the euro, the total saying yes had risen to 426.

The number saying no dropped from 327 to 278.

And there was also a fall in the don't knows.

The 8% swing in support of British entry was higher than the 2% swing in favour recorded in another survey a week ago.

That covered 400 British holidaymakers returning from Spain, France and Italy.

The main group campaigning for a no vote says the surveys are nothing like as positive as the euro supporters would like.

The findings contradict recent surveys which have suggested people using the euro abroad are no more likely, or even slightly less likely, to vote in favour of Britain joining the single currency.

The latest monthly poll by Barclays Capital last week suggested the "holiday effect" had failed to materialise.

The poll found 49% of people questioned would still vote against joining the euro, with 36% in favour, the joint worst result since the poll started.

The No Campaign claims this reinforces the suggestion in two polls last month - by MORI and GFK - that there may be a "reverse holiday effect".