Thousands of refugees could be left in "legal limbo" as European countries adopt different border rules to deal with the record influx of migrants, the UN refugee agency (UNHCR) has warned, according to BBC News.

It has called for the establishment of big European-run reception centres in countries where migrants are arriving.

The statement came as Germany imposed controls on its border with Austria.

European interior ministers are to hold an emergency meeting on the migrant crisis later on Monday, September 14.

They are due to discuss plans to spread 160,000 asylum seekers across 23 EU states through mandatory quotas. Preliminary talks over the weekend that aimed to draft a document for the meeting ended without agreement.

Europe as a whole is struggling to deal with an enormous influx of people, mostly from Syria but also Afghanistan, Eritrea and other countries, fleeing violence and poverty.

Many migrants have been refusing to register in countries such as Greece or Hungary, fearing it will stop them being granted asylum in Germany or other EU states.

The UNHCR said it was concerned that migrants seeking protection they are entitled to could "find themselves moving around in legal limbo".

It said that recent successive announcements of different border control measures by a number of European countries "only underlines the urgency of establishing a comprehensive European response".

This response must be based on the creation of effective reception centres which would "properly assist, register and screen people upon arrival in Greece, Italy and Hungary".

The UN warning came as Germany re-imposed border controls on Sunday, saying it was struggling to cope with thousands of asylum seekers arriving every day.