Greek Interior Minister Panagiotis Kouroumplis on Friday compared the overcrowded refugee camp at Idomeni to a World War II concentration camp.
"I am not reluctant to say that this is a modern Dachau," he told Skai TV during a visit to the camp on Greece's border with Macedonia.
The camp at Dachau near Munich was the first camp to be opened by Adolf Hitler's Nazi regime to hold political prisoners.
Kouroumplis said the miserable conditions in the Idomeni camp are enough to "turn your stomach" and attributed the situation to the sealing of the Balkan migration route.
Last week, the Balkan countries of Macedonia, Serbia, Croatia and Slovenia sealed their borders. Over the past year nearly 1 million people passed through Balkan countries en route to Germany and other wealthy EU countries.
The border closures have led to a massive buildup of migrants in Greece.
A large crowd of refugees remain at Idomeni in hope that they will eventually be allowed to continue north.
It is estimated that 12,000 people remain at the camp, despite it being designed for a brief stay of up to 2,000 people.