German Chancellor Angela Merkel is "appalled" by the latest migrant disaster in the Mediterranean and wants Europe to find "answers", her spokesman said Monday.

Merkel, "like millions of Germans", is appalled by Sunday's capsizing of a fishing boat off Libya in which more than 700 people are feared dead, Steffen Seibert told reporters.

Europe, "a continent which feels committed to humanity, must look for answers even when there are no easy answers," he added.