ROME (Reuters) - The presidents of Europe’s three main institutions on Thursday presented a bleak picture of the European Union, saying the 28-nation bloc lacked leadership and was descending into petty, nationalistic politics.

Slideshow ( 2 images )

“We have a lot of salesmen in the European Council and only a few statesmen,” said Martin Schulz, the president of the European Parliament, bemoaning the current crop of EU government chiefs who are struggling to overcome a string of crises.

Schulz joined European Commission President Jean-Claude Juncker and EU Council President Donald Tusk for a debate on the future of Europe in the room where the Treaty of Rome was signed in 1957, which laid the foundations of today’s European Union.

“The idea of one EU state, one vision ... was an illusion,” said Tusk, a former Polish prime minister, who is now tasked with finding consensus and cohesion amongst EU leaders.

Such unity has become an almost impossible mission at a time when hundreds of thousands of migrants are fleeing into Europe in search of a better life, sending a shockwave through the staid and conservative continent.

Britain, the Union’s second biggest economy, is due to hold a referendum in June on whether to withdrawal from the bloc.

Years of economic underperformance, particularly in the continent’s southern rim, have also frayed the fabric of European solidarity.

“PART-TIME EUROPEANS”

“We have full-time Europeans when it comes to taking and part-time Europeans when it comes to giving,” said a particularly downbeat Juncker, adding that the “part time” Europeans were often those who received most from EU funds -- a clear reference to new member states from the east.

Without naming names, Tusk also said that the newcomers were often the most opposed to finding a common policy on the migration crisis “sometimes in a very irritating fashion”.

Italy and Greece are the main ports of entry for the migrants but say they should then be sent on to other European countries to share the burden.

However, Poland, the Czech Republic, Slovakia and Hungary have rejected European Commission plans to introduce mandatory quotas of refugees and have accused Brussels of trying to blackmail them.

Juncker, a former Luxembourg prime minister who has been at the heart of EU policy making for three decades, reminisced about the time when Europe moved towards economic union and created the single euro currency.

“In former times we were working together ... we were in charge of a big piece of history. This has totally gone,” he said, complaining that EU citizens did not understand what the European Union was trying to do.

“This is fertile ground for the populists.”

Tusk, Juncker and Schulz are in Rome for the presentation of the Charlemagne Prize to Pope Francis on Friday. The prize is awarded to people who are seen to have furthered the cause of European unification.