Only around one in five Europeans and fewer than one in 10 Britons know that the EU has 25 member countries, according to a survey released Tuesday by the European Commission.

The Eurobarometer survey found that, on average, 23 percent of Europeans know the EU has comprised 25 countries since 10 mainly ex-communist states joined the bloc in May 2004.

Based on responses from around 1,000 people in each country from May 5 to June 11, 52 percent of respondents believed the Union has fewer than 25 members, five percent believe it has more and 20 percent had no opinion.

Citizens in only three countries scored 50 percent or more. Cypriots were top scorers with 58 percent and Slovenians had 51 percent, while exactly one in two residents of the tiny duchy of Luxembourg knew the right number.

Britons had the worst score: just eight percent knew the answer.

Given that few Europeans knew the right number of member countries, they obviously had difficulty saying who might be preparing to join soon.

Bulgaria (25 percent) and Romania (29 percent) are due to become members of the rich European club on January 1 and figured high up the list.

But Turkey, which has begun accession talks expected to take at least a decade and has no guarantee of membership, easily topped the list, with 42 percent of Europeans saying it was preparing to join.

10 percent thought new member Poland was about to take its place in the EU's ranks and nine percent thought that Hungary was a candidate.