A senior official with the International Organization for Migration says the massive increase in Syrians seeking refuge in Europe is largely driven by the inability of overwhelmed Mideast countries to cope with the crisis.

Hassan Abdel Moneim Mostafa said Wednesday that countries like Lebanon and Jordan "have reached their utmost limits," which forces Syrians to seek refuge elsewhere, contributing to the tide of migrants and refugees heading to Europe.

The vast majority of Syria's 4 million refugees reside in neighboring countries. Lebanon hosts 1.1 million, making them a quarter of its population.

The IOM says more than 464,000 migrants and refugees from various countries have crossed the Mediterranean Sea to Europe this year, and that 2,182 died on the way.