Members states reluctant to let Brussels get a look in on border controls

"Member states feel this is very much a national power," said one EU diplomat.

The commission had made the suggestion earlier this month as a quid pro quo for expanding the conditions under which countries can make border checks. Discussions on the proposals will continue next month.

The border debate was prompted by the surge in flows of migrants following the democratic uprisings in northern Africa.

The thousands of migrants arriving in Italy and Malta have highlighted the fragile trust-based nature of the 1995 Schengen Agreement that allows for passport-free travel in 25 European countries.

A Franco-Italian row over the fate of Tunisian migrants led both countries to call on the European Commission to make it easier to re-instate border checks.

The feeling that one of Europe's most beneficial and integrative projects is being undermined was intensified when Denmark on Wednesday announced it would start making customs checks on its borders with Sweden and Germany, citing rising crime concerns.

Malmstrom said she still had to thoroughly check the Danish deal before she could comment but speaking generally, she promised that the "defend and preserve" the Schengen agreement.

The commissioner said she would come forward soon with proposals to "clarify the circumstances" for when a member state could make border checks.

But she insisted that "bigger community involvement" is needed so member states "don't unilaterally invoke that mechanism."

Member states also promised to stick to plans to have a common asylum system agreed by next year.

The current differences mean that a refugee presenting one set of circumstances could have a 75 percent chance of being granted asylum in one member state but a less than one percent chance in another member state.

The most controversial aspect is reforming rules that state that the first country that an asylum seeker lands in is the country that has to process the application - a system that weighs more heavily on Europe's southern rim countries.

Critics of the EU's current debate on migration and border checks say it is being driven by hard-right parties in several countries that prey on latent fears about the possible effects immigration.

They say the system as a whole should be looked at, including strengthened external borders, ensuring common asylum procedures, and solidarity towards those countries that bear the brunt of refugees, such as Malta, the tiny Mediterranean EU member that has seen thousands of refugees arrive from Africa.