France's far-right National Front has caused a political "earthquake" in the country's European Parliament elections, with exit polls showing up to 25 percent of voters backing the party.
The anti-immigration, anti-EU party would win 23 to 25 of France's 74 seats in the European Parliament, according to average results from five polling institutes published on Sunday. The party currently holds three seats.
The centre-right UMP was in second place with a projected 20-21 percent of the vote, and the ruling Socialist Party was in third place with just 14-15 percent.
France's preliminary results were reflected in other European countries, with strong showings for anti-immigrant and anti-EU parties in Greece, Denmark and the UK.
Marine Le Pen, the National Front's leader, said: "The people have spoken loud and clear. They no longer want to be led by those outside our borders, by EU commissioners and technocrats who are unelected."
She also called for the French national assembly to be dissolved on the basis of the results.
"What else can the president do after such a rejection? It is unacceptable that the assembly should be so unrepresentative of the French people."
If the polls are correct, the EU election will be the National Front's biggest success in a nationwide poll.
"It's an earthquake," said Manuel Valls, the Socialist prime minister brought in by President Francois Hollande barely two months ago after the party suffered a similar rout in local elections.
Al Jazeera's Simon McGregor Wood, reporting from Brussels, said that the situation in France reflected a surge in support for anti-EU parties in other member countries.
“What we could see is the emergence of a new bloc that is anti the EU project. In Greece anti-EU parties are polling very well and in the UK, the anti-immigration party Ukip could provide a shock.
The AFP reported that anti-immigration Danish People's Party had won its country's EU elections.
“This could shake up the whole process," said our correspondent.
He noted however that the right-wing anti-immigration party in the Netherlands, the Freedom Party, was not doing as well as predicted, lying in fourth place in the polls.
Exit polls in Sweden showed the Feminist Initiative Party entering the European Parliament for the first time.
In Germany, Chancellor Angela Merkel's conservatives claimed victory despite strong gains for the centre-left Social Democrats. A new anti-euro party, the Alternative for Germany made its debut into the parliament.
Turnout averaged at 43.11 percent across the 28-nation European Union, observers said - fractionally higher than the 43 percent in 2009, which was the lowest rate ever.
“Voting has been on a slippery slope since 1979 but in the bigger countries this year turnout is up on the last election three to four percent in France and five percent in Germany," said McGregor Wood.