Eurosceptic 'earthquake' rocks EU elections
Marine le Pen: "The sovereign people have spoken loudly to say they want to be master of their own destiny"
Marine Le Pen's National Front has come first in France's elections to the European Parliament according to exit polls, in what PM Manuel Valls has declared a "political earthquake".
Eurosceptic parties appeared also to have made big gains in other countries, coming first in Denmark and Greece.
The centre-right EPP looked set to be the biggest bloc in parliament.
Turnout in the election was 43.1%, according to provisional European Parliament figures - up on last time.
That would be the first time turnout had not fallen since the previous election - but would only be an improvement of 0.1%.
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(based on exit polls/ provisional results)
- France National Front storm to victory - 26%, 25 seats; Centre-right UMP 21%; President Hollande's Socialists a poor third with 14% - lowest ever EP score
- Britain Eurosceptic UKIP heading for first place, with 29%. Conservatives and Labour about 23% each. Greens beating Lib Dems.
- Italy Centre-left PM Matteo Renzi scores strong 40%, fending off ex-comic Beppe Grillo's anti-establishment Five Star with 22%, and ex-PM Silvio Berlusconi's Forza Italia with 16%
- Germany Angela Merkel wins another election - 36% for her Christian Union, 27% for the centre-left SPD. Eurosceptic AfD score strong 7%.
- Greece Early results show far-left Syriza on 26%, PM Antonis Samaras' New Democracy on 23%. Far-right Golden Dawn set to get three MEPs, with 9%
"The people have spoken loud and clear," a triumphant Marine Le Pen told cheering supporters at National Front (FN) party headquarters in Paris.
"They no longer want to be led by those outside our borders, by EU commissioners and technocrats who are unelected. They want to be protected from globalisation and take back the reins of their destiny."
Provisional results suggested the FN could win 25 European Parliament seats - a stunning increase on its three in 2009.
The party also issued an extraordinary statement accusing the government of vote-rigging.
Hard-left gainsAcross the board, the centre-right European People's Party was set to win 211 out of the 751 seats, with 28.1% across the bloc, according to estimated results issued by the European Parliament. That would make it the biggest group - but with more than 60 seats fewer than before.
That put it ahead of the Socialist group with 193 seats (25.7%), Liberals with 74 (9.9%) and Greens 58 (7.7%).
The right-wing Eurosceptic Europe of Freedom and Democracy group, incorporating the UK Independence Party (UKIP), looked to have about the same number of seats as last time, but there looked set to be a rise in the number of non-attached right-wing MEPs boosting the Eurosceptic camp.
UKIP leader Nigel Farage was predicting that his party would come first in Britain, saying: "The inevitability of European integration ends tonight."
The anti-bailout hard-left group in parliament was set to make big gains, largely thanks to Syriza in Greece and United Left in Spain, gaining about 12 seats.
At the moment the exit poll predictions in France are the most striking story on this election results night. Even the prime minister says the Front National is heading for victory - a political earthquake indeed. Is the UK about to follow suit on the political Richter scale?
Elsewhere exit polls suggest the radical left anti-austerity party Syriza has come first in the elections in Greece. While in Italy it looks set to be a close fight between the Democratic Party of the Prime Minister Matteo Renzi (running in his first national campaign) and Beppe Grillo's Five Star Movement.
So plenty of anti-establishment parties are poised to increase their share of the vote, as predicted. It could well make for a more interesting more rumbustious European parliament. Even so there will still be a clear pro-European majority.
The question for mainstream parties on the centre-right and the centre-left is how they intend to respond to the sense of dissatisfaction with "politics as usual" that many voters have clearly expressed.
Martin Schulz, the former Socialist president of the European Parliament - said of the FN victory: "It's a bad day for the European Union, when a party with a racist, xenophobic and anti-Semitic programme gets 25% of the vote."
The election is the biggest exercise in multi-national democracy in the world. The vote will affect the lives of the EU's 500 million citizens.
The parliament's powers have expanded since the last election in 2009, and it is hoping to have a decisive say in who gets the EU's top job, president of the European Commission.
The frontrunner for that will now be EPP candidate Jean-Claude Juncker - though that would need the approval national government leaders, which is by no means guaranteed, correspondents say.
You can follow full coverage with all the latest updates at bbc.co.uk/vote2014.