LUXEMBOURG (Reuters) - EU leaders promoting utopian “illusions” of a united Europe have lost touch with its peoples and risk losing out to euroskeptic populists bent on breaking up the bloc, European Council President Donald Tusk said on Monday.

Tusk, who will chair a summit of EU leaders next month days after Britain votes on whether to leave the Union, made the outspoken criticism in a speech to fellow conservatives from EU countries, including many supporters of a more federal Europe.

“It is us who today are responsible for confronting reality with all kinds of utopias -- a utopia of Europe without nation states, a utopia of Europe without conflicting interests and ambitions, a utopia of Europe imposing its own values on the external world,” the former Polish prime minister said.

“Obsessed with the idea of instant and total integration, we failed to notice that ordinary people, the citizens of Europe, do not share our Euro-enthusiasm. Disillusioned with the great visions of the future, they demand that we cope with the present reality better than we have been doing until now ... Euroskepticism (has) become an alternative to those illusions.”

Much of the British campaign to leave the EU in a referendum on June 23 has focused on fears of greater integration at the expense of national sovereignty -- concerns that are also strong in Tusk’s native Poland, where his own center-right party lost power last year to euroskeptic, right-wing opponents.

He made no explicit mention of the Brexit debate in his speech in Luxembourg to an audience that included German Chancellor Angela Merkel and EU chief executive Jean-Claude Juncker at a meeting of the European People’s Party, an alliance that is the biggest bloc in the European Parliament.

However, Tusk, who has long defended states’ rights against centralizing forces in Brussels, has called a British departure a major risk for the EU. He urged leaders to change tack on confronting anti-EU forces, which include strong movements in France, the Netherlands, Hungary and several other countries:

“The specter of a break-up is haunting Europe,” he said. “A vision of a federation doesn’t seem to me like the best answer to it.”