In its new migration report released on Tuesday, the OECD said that an estimated 350,000 to 450,000 people could be granted refugee or similar status in Europe in 2015, more than in any refugee crisis in Europe since World War II.
It said 700,000 asylum seekers had been registered so far this year, and that this figure was going to climb to 1 million by the end of the year. This compares with the 630,000 asylum registrations in 2014.
Germany was receiving the most asylum seekers of any European country in absolute numbers, with Austria, Sweden and Switzerland having the highest rate in per-capita terms, according to the report.
Hungary also had many asylum applications in the first half of 2015, the report said, but added that most refugees ended up moving on to wealthier northern European nations.
Problem of diversity
The report emphasized that the current refugee inflow was unprecedented not only in numbers, but also in the diversity of the source countries, saying that this diversity would make it more difficult to process asylum applications and also to integrate accepted refugees in the long term.
Although Syrians, Afghans, Iraqis, Serbians, Kosovars, and Albanians made up some 60 percent of refugees, a great number of people are also fleeing from a range of African countries, in particular Eritrea, Nigeria and Somalia, the report said.
The number of unaccompanied children making the journey to Europe had also grown, another characteristic setting this crisis apart from other previous ones, the OECD said. It said child asylum seekers posed a particular problem, as they require special housing, care and education.
The OECD warned that the situation in the main source countries was unlikely to stabilize in the near future, meaning that continued large inflows can perhaps be expected in the years to come.
Fast integration 'essential'
The OECD however pointed out that Europe was now better placed to cope with large migration movements, having set up legal provisions and institutions to deal with an increase in asylum seekers and other migrants.
It emphasized that although processing and supporting refugees was costly at first, history has shown that refugees and migrants can end up making valuable contributions to the countries that take them in and paying more in taxes than they have received in individual state benefits.
However, for this to happen, countries had to ensure that immediate measures were in place - including language training, individual skills assessments, help with health and social problems and programs developed with employers to boost migrants' job chances - to foster integration. According to the report, special focus should be placed on the integration of migrant women.