Among the leaders of the effort to "unite the right" are France's Marine Le Pen and Italy's Matteo Salvin
Many fear the May 26 vote will be a wake-up call for Brussels on the reality that Europe's anti-immigration and blood-and-soil patriotic forces have moved from the fringes to the mainstream. Once considered outsiders, they could now end up with one fifth or more of the seats, allowing them to shift the tone of political discourse and make a claim for legitimacy.
Key players are Marine Le Pen's National Rally (NR) in France and the Italian League of Matteo Salvini, who is hosting a meeting of like-minded right-wing groups in Milan on Monday.
In the EU's top economy, the Alternative for Germany (AfD) has become the biggest opposition party by railing against Chancellor Angela Merkel and her 2015 decision to allow a mass influx of asylum seekers. On Saturday the AfD will gather in the city of Offenburg to present its election programme, which calls for "a Europe of fatherlands" and opposes the EU's immigration, financial and climate policies.
On Monday in Milan, Italian deputy PM Salvini will follow up and gather allies from across Europe to try to lay the foundations for a future hard-right grouping in the now 751-member European Parliament.
Salvini and Le Pen also agreed to call another meeting in May, after they met in Paris on Friday, a NR source said.
"The leaders are considering a common manifesto to close the electoral campaign and announce the start of a new Europe," said a spokesman for Salvini.
International of nationalists?
So far, Europe's right-wing nationalists have been divided into three blocs and a tangled web of alliances in the legislature that moves between seats in Brussels and the French city of Strasbourg. They are the Europe of Nations and Freedom (ENF) group, which includes the RN and League, the European Conservatives and Reformists (ECR) and the Europe of Freedom and Direct Democracy (EFDD).
