But leaving the door to the EU 'wide open' was not possible, he said

He added the EU could consider welcoming a 'defined group' of migrants

Donald Tusk said the EU must work out policy for sending migrants back

The EU cannot welcome all migrants fleeing to its shores and will have to work out a new return policy to tackle the problem, European Council president Donald Tusk has said.

'I am realistic and I think that first of all we have to work out a new return policy, which would be a policy of sending them back,' he said in an interview in Polska The Times on Monday.

'In a responsible manner we can talk about welcoming only a defined group of immigrants. Those who say let's open the door widely are cynical since they know it is not possible.'

A group of migrants from Africa receive water at a detention centre in Tripoli after being arrested before boarding boats to try and reach Europe

A series of disasters in the Mediterranean in which hundreds of migrants from North Africa have drowned after attempting to cross the sea in overcrowded and unsafe vessels has sharpened international focus on the issue of migration into Europe.

The European Commission is planning to legislate before the end of the year to ensure the burden of housing immigrants is shared across the bloc, according to binding quotas based on criteria such as economic health and population.

His comments come a day after the EU's foreign policy chief pushed for a naval mission in the Mediterranean to target Libyans smuggling people to Europe.

The European Union ultimately wants to capture smugglers and destroy their boats off the Libyan coast to help it tackle the rising number of migrants fleeing war and poverty in North Africa, but many EU countries want United Nations authorisation to act.

EU foreign policy chief Federica Mogherini said EU foreign and defence ministers 'will be taking the decision to establish the operation at sea to dismantle the criminal networks that are smuggling people in the Mediterranean'.