What was needed, the UNHCR spokesperson added, was "a unified approach that moves away from some of the more recent actions where we have seen States unilaterally seeking to harden or strengthen borders or restrict access to the asylum space".
Based on the success of an EU-Turkey deal that outsourced responsibility for strengthening Europe's borders refugees to the Turkish government in exchange for billions in refugee aid, EU leaders want to expand the idea with "regional disembarkation platforms" in Africa.
According to summit conclusions, which was belated due to Italian Prime Minister Guiseppe Conte insistence on some lines, member states of the European Union (EU) will, on a voluntary basis, set up so-called "controlled centers" to host and transfer migrants that landed on EU shores.
Earlier in the evening, Italy's had refused to sign the joint conclusions - which also touched on defense, trade and technology - amid concerns that the bloc wasn't doing enough to relieve the burden of migration in front-line Mediterranean countries.
"And these proposals and this Parliament has been completely ignored by the agreement of the member states in the European Council".
As Italy's new populist government threatened to block progress on other, uncontroversial issues until the migration text was addressed to its satisfaction, European leaders thrashed out the topic for nine hours before finally reaching an agreement around 5 am on Friday.
In those centres, "rapid and secure processing would allow, with full European Union support, to distinguish between irregular migrants, who will be returned, and those in need of global protection, for whom the principle of solidarity would apply".
In front of a rowdy Parliament on Thursday, she essentially conflated her own fate with that of the union.
Beyond demands from Italy, German Chancellor Angela Merkel also faced intense domestic pressure to find a breakthrough to stave off a government crisis at home.
But they warn that key elements of the deal remain vague and that it could create new problems for a bloc badly split over how to deal with people fleeing violence and poverty in Africa, the Middle East and South Asia.
Migrants are crossing the Mediterranean in far lower numbers than at their peak in 2015, but the influx remains a source of bitter contention in Europe.
The aim is to discourage migrants from boarding smuggler boats bound for Europe.
The plan calls for stronger controls at the European Union's external borders; for more cooperation, funds and resources for the countries of origin and transit of migrants; and for a more decisive fight against human trafficking organizations. "But there's nearly a fantasy island element to it".
In recent weeks, US and Mexican officials have been discussing a somewhat different "safe third country" agreement, which could require Central American migrants crossing through Mexico to apply for settlement there, and allow the United States to send back asylum seekers who do not do so.
Chico Harlan reported from Rome. Greek Prime Minister Alexis Tsipras told the Financial Times on Wednesday that he was open to such an agreement.