Up to 750,000 refugees could seek asylum in Germany this year, according to reports.

Berlin had projected some 450,000 asylum seekers would arrive in Germany in 2015 but has now revised that estimate to 650,000 or higher, the BBC reports.

The number of asylum seekers across Europe has risen dramatically due to conflict in Africa and the Middle East, with high numbers of migrants travelling to Germany from Syria and the Balkans.

UN High Commissioner for Refugees Antonio Guterres has called on more countries across the continent to share the burden of the increased number of refugees.

"It is unsustainable in the long run that only two EU countries, Germany and Sweden, take in the majority of refugees," he told German daily Die Welt.

Germany is the most popular destination for people seeking asylum in the EU.

Close to a quarter of a million refugees have crossed the Mediterranean already this year, arriving in Greece and Italy and often moving on to other regions. Greece has called for more assistance in managing the problem, with 21,000 refugees arriving in the past week.

In 2014 there were 202,645 asylum applications in Germany. In the same period there were 1,450 in Ireland.