21 heads of state of various European Union member-states have signed a new manifesto arguing for more integration in the political bloc and a “stronger Europe” — interpreted as a response to the rise of eurosceptic, pro-sovereignty populist parties.

Among the signatories, according to Italian newspaper Il Giornale, are several monarchs such as those of Sweden, Spain, the Netherlands, Belgium, and Denmark, as well as many presidents, including Italian president Sergio Mattarella.

“European integration has contributed to realising the centuries-old hope of having peace in Europe after unbridled nationalism and other extreme ideologies have brought Europe to the barbarism of two world wars,” the manifesto claims.

“The 2019 elections are particularly important: it is you, the European citizens, who will choose which path the European Union will follow,” the signatories note, adding: “Europe is able to accommodate a very wide range of opinions and ideas. But there must absolutely be no return to a Europe where countries are no longer equal partners, but adversaries.”

The heads of state also argue that the European Union must be strengthened, saying the political bloc must be, “A Union that has common institutions, a Union that constantly reviews its work with a critical eye and is able to reform itself, a Union that is built on its citizens and its Member States as a vital base.”

The manifesto is seemingly the latest attack by establishment figures on the rising populist movement in Europe. The European Commission, particularly its unelected president, Jean-Claude Juncker, have also attacked populists, including threatening to block them from Commission positions regardless of the election outcome later this month.

Last month, the European Union’s own election predictions showed a massive expected surge for the populists and other conservative eurosceptics to the point where they could become the second largest political force in the European Parliament.

Follow Chris Tomlinson on Twitter at @TomlinsonCJ or email at ctomlinson(at)breitbart.com