Anti-EU parties are likely to form the second largest bloc in the European Parliament after next month’s elections, a study of polling trends by a European think tank has found.

With support for anti-EU parties on the right and the left increasing in many parts of Europe, the European Council on Foreign Relations says that the new parliament is likely to be dominated by three major coalition blocs – the centre-right European People’s Party (EPP) group, the centre-left block based around the alliance of Socialists and Democrats and what it calls the “anti-European” bloc, comprised of several elements.

However, the think tank also suggests that for the first time a combined “grand coalition” of the EPP and the left-wing bloc will not have a majority in the parliament, handing a potential king-maker role to a fourth bloc: the centrist Alde group, which includes Fianna Fáil.

The think tank, which published the results of the research in a paper authored by Irish academics Michael Marsh, Kevin Cunningham and London School of Economics professor Simon Hix, says that the anti-EU forces could be the second largest group whether or not the UK participates in the elections.

The UK says it will hold European parliament elections if it remains a member of the EU at the time, although British prime minister Theresa May is expected to make another attempt in the coming weeks to get the withdrawal agreement through the House of Commons, meaning that the UK could then leave the EU. This would avoid the necessity to hold elections there.

The report, which was based on various types of polling data from EU countries, finds that anti-EU parties could have as much as 35 per cent of the seats in the new parliament, though it acknowledges that such disparate parties – with some coming from the far-right, others from the far-left – are unlikely to work coherently together.

However, their presence in the parliament and their opposition to many EU initiatives could force the other pro-EU parties to work together, with the centrist Alde group, including French president Emmanuel Macron’s En Marche party, occupying a pivotal role.

Irish seats

Country-by-country breakdowns of the research show that the think tank reckons that in an election with 11 MEP seats in Ireland (13 seats will be filled if the UK leaves; 11 if not) Fine Gael will win three seats; Fianna Fáil will win two; Sinn Féin two; Independents three; and the Greens one.

The Council on Foreign Relations says that the fractured nature of the next European Parliament means that pro-European parties will have to learn to co-operate across traditional political boundaries.

The think tank’s research suggests that voters want the parties to co-operate on issued such as affordable housing, inclusive economic growth, social integration and climate change.

“Pro-European parties must disseminate their messages in the next month and, immediately after the European Parliament election, begin to deliver on their promises,” the report says.

Susi Dennison, senior policy fellow and director of the European power programme at the European Council on Foreign Relations, warned that a new parliament “that is finely balanced between anti-Europeans and divided pro-European forces presents a real risk of paralysis at the centre of the EU.”