Mitsotakis's remarks come as many people in Santorini spent Sunday night outdoors, amid fears of potential damage to buildings during the quakes. Some focal points of the tremors have been recorded at a depth of just 2km (1.2miles) below the surface.

The strongest earthquake recorded was magnitude 4.6 at 3:55 p.m. Sunday, at a depth of 14 kilometers (9 miles), the Athens Geodynamic Institute said.

Tremors between Santorini and Amorgos since Friday led to school closures in Santorini, Ios, Amorgos, and Anafi, as authorities monitor the seismic activity.