Voters will have to wait until Sunday to discover who they have elected to the European parliament.

Although the British public finished casting its ballots on Thursday, polls are taking place throughout the continent this weekend with declarations not supposed to be made in any member state until all EU countries have finished voting.

The rule is in place to prevent results or exit polls in one nation having an affect on voting in another.

But the major parties will now be reviewing their campaigns in a contest that was evenly balanced between the big three and the UK Independence Party.

The Green Party will also be hoping to make gains when the result is declared on Sunday evening while former Labour MP George Galloway's new Respect coalition could make a mark.

However due to EU expansion Britain is losing nine of its previous allocation of 87 MEPs, making the outcome more unpredictable.

For the purposes of the election the UK is divided up into 12 constituencies, each of which will return multiple MEPs to the Brussels parliament.

The distribution of seats is as follows:

• Eastern: 7
• East Midlands: 6
• London: 9
• North East: 3
• North West: 9
• South East: 10
• South West: 7
• West Midlands: 7
• Yorkshire and the Humber: 6
• Scotland: 7
• Wales: 4
• Northern Ireland: 3

Under the proportional representation system in operation, voters can cast one vote for a party or independent candidate.

Each political party prepares a list of candidates ranked in order to match the number of seats to be filled in that region.

Once votes are counted, the first seat is allocated to the party or independent candidate with the highest number of votes. If an independent candidate is highest, the seat is allocated to that individual. If a party wins, the seat is taken by the person on top of that party's regional list.

After the first allocation, a winning party's total number of votes is divided by two and the second seat is allocated to the next party or independent candidate with the highest number of votes.The process then continues until all seats have been allocated.