He noted that 160,000 asylum seekers were to be taken from Italy and Greece by September, but that the latest numbers were still “very low” - reported euobserver.
“You have not a lot of time in front of you, but do it as soon as possible,” he said, addressing non-compliant EU states.
“This is a common European policy that we adopted in Luxembourg two years ago. It is mandatory,” he said.
He added that lack of solidarity on issues such as migration could “put in question the very existence of the European Union”.
Avramopoulos spoke at an informal EU meeting in Estonia that discussed Italy’s appeal for help following a surge in arrivals from Libya.
Other EU states declined to open their ports to migrants, instead saying that non-refugees should be deported more quickly and that NGO rescue boats should follow a new code.
Avramopoulos said he had “called on member states to do more on relocations” at Thursday’s meeting.
His previous appeals having gone unheeded, the commissioner added: “Let’s see whether it will be said many times in the future.”
EU states have so far relocated some 20,000 people from Italy and Greece.
The Commission has launched legal action against the Czech Republic, Hungary, and Poland for boycotting the scheme.
As of 3 July, Austria, Bulgaria, Denmark, Estonia, Ireland, and Slovakia had not relocated a single person from Italy.
Germany and France were miles away from their full legal commitments, with Germany 20,477 relocations short and France 15,935 behind.
Spain (8,254 short), the Netherlands (3,891), Romania (3,546), Sweden (3,100), Belgium (3,031), and Portugal (1,561) were also heading for major violations.
Avramopoulos defended the EU’s decision to step up expulsions of economic migrants and to create rules for NGO rescues.
“Tens of thousands of people are economic migrants … they have to be returned to the country they came from,” he said on Thursday.
He said the Commission was waiting for Italy to draft a code of conduct for NGO rescues prior to its EU imprimatur.
The Estonian interior minister, Anders Anvelt, who chaired Thursday’s meeting on behalf of his country’s EU presidency, said the NGO code was needed for coordination.
“If you had a forest fire and you had NGOs and then national rescue workers and there was no coordination between them, I don’t think there would be a good result,” he said.
Human Rights at Sea, a UK-based charity, said on Thursday it had seen a leaked copy of the draft Italian code.
There was “a distinct lack of ... explicit reference to the need to save life at sea” in the draft, the charity said.
It said that NGOs who refused to sign could be denied access to Italian ports.
It also cited Italian coastguard figures for April which said that NGOs rescued 5,015 people from sea that month.
Commercial ships rescued 3,523 people and Italian authorities rescued 3,225, while two EU operations, Frontex and Sophia, rescued 937 between them.
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