UNITED NATIONS (AFP) - UN Secretary General Ban Ki Moon appealed to world governments to share the burden of taking in refugees after more than 700 migrants were feared dead in the latest Mediterranean boat tragedy.

Ban said he was "shocked and deeply saddened" by reports of the shipwreck off the coast of Libya and noted that it was the latest in a line of incidents in the last week.

He "appeals to the international community for solidarity and burden-sharing in the face of this crisis," said a statement from his spokesman.

At least 1,600 people have died this year by attempting to cross the Mediterranean, making it the "world's deadliest route used by asylum seekers and migrants," he said.

Governments must not only improve rescue at sea but also "ensure the right to asylum of the growing number of people worldwide fleeing war who need refuge and safe haven," he added.

Europe has been facing massive flows of migrants arriving from the Middle East and Africa, fleeing poverty and war.