There must be a pan-European policy on migration and asylum, or risk the European Union falling apart, according to the EU’s top migration official.

Dimitris Avramopoulos, the European Commission’s senior migration official, told a debate in Brussels on Thursday that the migration crisis is testing the values on which the EU was founded.

During an EU committee of the regions debate on 3 December, Avramopoulos, mayor of Athens from 1995-2002, criticised the majority of European countries for failing to do enough to help refugees turning up on the continent’s shores after fleeing war, poverty and persecution. Just eight of the 28 EU member states who originally agreed to a fairer distribution of refugees have taken action to resettle people in their own countries, he said.

Regions in the south and east of Europe have been left shouldering most of the burden in the influx of new arrivals. Not only does this test the EU principle of solidarity but also the principle of free movement, according to Avramopoulos. He added that the crisis could threaten the Schengen agreement for a borderless Europe, which he described as the EU’s biggest achievement.

During the debate, the committee agreed to back the European commission’s agenda on migration, which calls for stronger border controls and a relocation system to resettle refugees across the EU.

The committee, the EU’s assembly of local government representatives, has also called for far greater recognition of the role regional and local authorities can play in tackling the crisis, and direct access to European funding for integration and resettlement schemes.

Avramopoulos said anyone resisting the arrival of migrants should remember that Europe is an ageing continent and needs to attract new people, as well as develop strategies to send home those who enter illegally.

The confusion in terminology between refugees and economic migrants has caused problems, he said. “We must not listen to nationalists and to xenophobic groups that unfortunately are gaining more and more ground in Europe right now because this misconception exists.”

The European parliament’s co-rapporteur on migration, Cécile Kashetu Kyenge, also lambasted the “short-sighted, egotistical policies of certain member states”. Kyenge, a Congolese-Italian politician and member of the European parliament, said the EU should promote a bottom-up approach that involved local authorities in planning and implementing migration policy.

“It is up to them, in practice, to find a way to maintain social cohesion in their communities and to prevent social tensions and extremism,” she said.

Some members of the committee voiced more hostile views on the crisis facing Europe. Anna Magyar, a Hungarian politician from Csongrád County, which shares a border with Serbia and has seen clashes between local authorities and refugees with police using tear gas and refugees declaring hunger strikes, said many of the migrants entering Europe were simply looking for a better standard of living.

“It needs to be made absolutely clear that the boat is full,” she said. “Member states have obligations to their own citizens. When are we going to start protecting our own citizens against the massive flows of illegal migrants?”

French politician François Decoster, who comes from Maire de Saint-Omer, about 40km north of Calais, said local authorities are much better placed to determine local need. Speaking to the Guardian, Decoster said the commissioner and French prime minister had visited his region to announce construction of 1,500 shelters. “At the time we had 3,000 people there. The number announced for building shelters was already insufficient,” he said.

Decoster called for local authorities to be allowed to bypass their national governments and apply for direct funding from the EU. Each of the 28 EU member states has its own policy; this is one of the reasons why the situation at the border between France and England in Calais is so difficult to resolve, Decoster said.

Decoster, who has been working on the Committee of the Regions’ (CoR) response to the European commission’s agenda on migration since the spring, said local and regional governments across Europe are given too little political say, too little funding and too little backing. “That must change,” he said.

Donald Tusk, president of the European Council, which is made up of the leaders of EU member states, praised CoR members for being at the frontline of European politics and dealing directly with the migrant influx. Tusk, the former Polish prime minister, dropped out of the plenary line-up, but in a recorded video message he told delegates that the EU faced existential threats and needed to decide “what kind of political community we are”.

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