Between January and November this year, Frontex detected 1.55 million illegal border crossings at the external borders of the EU.

In November alone, 276 000 illegal border crossings were detected, which represented a decrease of 7000 compared to the same month last year.

The number of migrants arriving in Greece in November dropped by more than a half compared to the previous months.

Their number dropped to 108 000 in November, recording the first month-on-month decrease this year.

However this was still the highest number of arrivals in Greece in the month of November.

The worsening weather conditions, which make the sea crossing between Turkey and the Greek islands more dangerous, are possibly the main reason for the drop in the number of migrants.

Another factor likely to be contributing to the drop might be the more restrictive border control policy, which has been implemented on the Western Balkans route.

Despite the drop in November, the number of people arriving on the Greek islands increased to more than 715 000 in the first eleven months of this year, which represented a sixteen-fold growth compared to the same period last year.

Syrians remained the top nationality of migrants, followed by citizens from Afghanistan and Iraq.

The number of migrants detected on the sea crossing between Libya and Italy in November stood at 3200, decreasing for the fourth consecutive month and dropping by two-thirds compared to the previous month.

So far this year, a total of 144 000 illegal border crossings have been detected on the Central Mediterranean route, which represented a decrease of 10 % compared to the same period in 2014.

Citizens of Eritrea and Nigeria continue to constitute the largest share of migrants arriving to Italy.

The number of illegal crossings detected on the Western Balkans route in November dropped to 164 000, which represented a decrease  of a fifth compared to the previous month.

In the first eleven months of this year, a total of 667 000 illegal border crossings were detected on the Western Balkans route, which represented an increase of 22 times compared to the same period last year.

Most of the migrants detected on the Western Balkans route at the borders  of Hungary and Croatia with Serbia had previously arrived on one of the Greek islands.

They then left Greece and the EU through the country's northern land border with Macedonia, continuing through Serbia, re-entering the EU in Hungary or Croatia.