European voters go to the polls this weekend with far-right, nationalist and anti-EU groups set to double their parliamentary representation and threaten the dominance of the pro-union political mainstream.

Europe’s ability to influence major world events beyond its own frontiers, on issues ranging from Iran’s nuclear programme to the aftermath of the Arab Spring and human rights across the world, could be severely diminished if anti-EU elements gained a strong presence in the twin Brussels and Strasbourg assemblies.

Recent polls suggest a slim majority for centre-right candidates, socialists snapping at their heels. But a major concern is that the far right, including the anti-immigration, anti-Islam nationalist parties of Marine Le Pen in France and Geert Wilders in the Netherlands, could win a quarter of the seats, form an alliance, obtain access to central funding and become steadily more powerful.

Amid forecasts of record abstention by blase voters, all French opinion polls put Ms Le Pen’s Front National (FN) party in first place. In Britain, the UK Independence Party (Ukip), whose popularity is seen as part of Europe’s drift to the extreme right despite its efforts to distance itself from the FN, is also experiencing a late surge of support as it aims to capture the biggest share of UK votes cast.

Ms Le Pen’s strategy of dédiabolisation – the “de-demonisation” of her party – has brought her remarkable success in elections at all levels.

Perhaps even more worrying for those seeking harmonious community relations, she may not even need such nuances. Fed up with Europe and the failures of left and right governments, newly attracted FN voters talk unashamedly of giving the “extreme right” a chance.

Ms Le Pen’s father, Jean-Marie, is still the party’s honorary president and an EU election candidate. Yet if dédiabolisation is necessary, this would be a consequence of his reputation for racist, anti-Semitic rhetoric.

Mr Le Pen struck a familiar tone this week, talking at an election rally in France’s second city, Marseille, which has a large Maghrebin comunity, of a “cataclysmic phenomenon” confronting the whole of Europe.

He said mass immigration threatened to replace indigenous populations with foreigners “if we do not gain power soon enough to put an end to decades of political decadence”.

“This phenomenon is aggravated in France by a religious aspect: most of these immigrants are Muslims, a religion with a conquering vocation, all the more so because it feels strong and numerous.”

His daughter, present at the rally where she warmly embraced her father, portrays herself as France’s saviour. Other assessments are more mixed. The left-of-centre news magazine Le Nouvel Observateur calls her a halfway house between Joan of Arc and the Russian president Vladimir Putin.

A senior, unnamed FN official told the magazine Ms Le Pen believes Mr Putin has handled the Ukrainian crisis “magnificently”. He added that she especially admires his “muscular style of government, his defence of ‘Russia eternal’ and his challenge to US world leadership and ultra-liberal global capitalism”.

A measure of how seriously the rise of Ukip is viewed in Britain, which goes to the polls Thursday, three days ahead of most of the other EU 28 member countries, is evident in the shrill terms in which mainstream politicians discuss it.

George Osborne, the British finance minister, warned yesterday that Ukip wanted to “pull up the drawbridge and shut Britain off from the world”.

Anxious to avoid alienating his own Conservative party supporters, many also highly Eurosceptical, he took care to include the left in his criticism.

But disenchantment with the EU stretches across the continent. People are fed up with dwindling spending power, stubborn or rising unemployment, security fears and governments’ inability to curb immigration.

In the Netherlands, which also has a large Maghrebin population, the Dutch Freedom Party of Geert Wilders is likely, on recent surveys, to take 18 per cent of votes, more than the candidates of the ruling coalition partners and similar to projected support for centrists.

Mr Wilders, who once compared the Quran to Hitler’s Mein Kampf and said it was not Muslims but Islam that he hated, set the tone for nationalist responses to common preoccupations during a speech in The Hague in March.

He asked whether people listening to him wanted more or fewer Moroccans. When the crowd responded with chants of “fewer, fewer”, he replied: “Good. We’ll arrange that.”

This week, Mr Wilders symbolically vandalised the EU flag in front of the parliamentary building in Brussels, cutting out one of the 12 gold stars and replacing it with the Dutch flag.

As part of his assault on a unified Europe, Mr Wilders hopes to create an anti-EU parliamentary faction bringing together like-minded parties from different countries. Its aim, according to the online newspaper EUobserver.com, would be to “pull apart the EU from within”.

Colin Randall, thenational.ae