(Reuters): Italy rebukes EU leaders as 'time wasters' on migrants plan

* Decision on how to distribute migrants delayed

* Debate described as 'controversial' at EU summit

* EU summit to replace mandatory plan with voluntary one (New throughout, adds Italian, diplomatic comment)

By Robin Emmott and Francesco Guarascio

BRUSSELS, June 25 (Reuters) - Italian Prime Minister Matteo Renzi rebuked fellow EU leaders on Thursday for failing to agree a plan to take in 40,000 asylum-seekers from Italy and Greece, saying they were not worthy of calling themselves Europeans.

EU leaders are divided over a growing migrant crisis in the Mediterranean and have largely left Italy and Greece to handle thousands of people fleeing war and poverty in Africa and the Middle East.

"If you do not agree with the figure of 40,000 (asylum seekers) you do not deserve to call yourself Europeans," Renzi told an EU summit in Brussels. "If this is your idea of Europe, you can keep it. Either there's solidarity or don't waste our time," he said, according to a person who attended the meeting.

Another official described the debate as "controversial". Much of the tension appeared to be about ensuring that the migration plan was voluntary, not mandatory as the European Commission had initially suggested.

Stung by deaths this year of almost 2,000 migrants trying to reach Europe by boat, the European Union has promised an emergency response but not national quotas for taking people.

According to a draft final summit communique, governments would agree to relocation over two years from Italy and Greece to other member states of 40,000 people needing protection. It said all member states will participate.

As EU leaders tackled the issue over dinner, some eastern and central European countries, which are reluctant to take refugees, sought guarantees that the system be temporary and voluntary.

"We have no consensus on mandatory quotas for migrants, but ... that cannot be an excuse to do nothing," said Donald Tusk, president of the European Council who chairs summits. "Solidarity without sacrifice is pure hypocrisy."

The criteria to share migrants among member states must be decided by the end of July, the draft communique said. Such factors as the size of a member state's economy and population will be considered.

The criteria system would replace unpopular proposals for mandatory quotas on each country.

The EU will also commit to resettle 20,000 refugees directly from countries such as Syria, Iraq or Afghanistan.

EU governments have been divided about boat migrants crossing the Mediterranean. This has strained the EU's commitment to its Schengen agreement on passport-free travel.

This week, Austria threatened to reimpose controls on its border with Hungary and Britain called for more security around the French port of Calais. Hungary has called the European Commission's relocation plan "absurd", while Spain wants a bigger focus on returning migrants to countries of origin.

But many governments agree the system for tackling migration is broken, with a huge burden on countries such as Italy and impoverished Greece.

EU leaders agreed to strengthen mechanisms to repatriate migrants who cannot claim asylum in Europe.

"We need treaties for readmitting people so that traffickers are clear that those they send illegally will be returned home," Spanish Prime Minister Mariano Rajoy told reporters. (Reporting by Robin Emmott; editing by Andrew Roche and David Gregorio)