European Union leaders have agreed to relocate 40,000 migrants from Italy and Greece to other EU countries over the next two years, in an effort to share the burden of a growing migrant crisis.

EU President Donald Tusk said the agreement was reached after an overnight summit early Friday, to show "solidarity with frontline countries."

French President Francois Hollande said the EU will also resettle 20,000 refugees, "essentially from Syria and Iraq, who at this moment are in camps and who will be reinstalled in Europe."

The migrant crisis has caused tensions among EU countries.