At least one person was killed on Sunday when a blaze which broke out on Lesbos island, prompting fresh calls for government action.
Greece has announced plans to return thousands of migrants by the end of next year, after a deadly fire at its largest camp on Lesbos island.
The UN refugee agency estimates that the Moria refugee camp, with an official capacity of 3,000, currently houses around 12,000 people in tents and shipping containers.
Government spokesman Stelios Petsas confirmed that the Council of Ministers had discussed an overhaul of Greece's migration policies on Monday.
Changes to be implemented include a strengthening of the country's border guards, with increased patrols at sea, and the construction of closed pre-concession centres for illegal migrants not yet entitled to asylum.
Greece also plans to increase the immediate return of migrants to "safe countries". More than 1,800 migrants were returned by Greece since early 2015, but Stelios Petsas announced aims to increase this number to 10,000 by the end of 2020.
Citing the nationalities of new arrivals, Petsas said Greece was now dealing with “a problem of migration, rather than a refugee problem.”
Speaking at the UN General Assembly last week, Prime Minister Kyriakos Mitsotakis said Greece was reaching the limit of its ability to tackle the problem.
Mitsotakis had urged Turkey to respect an agreement with the EU to stem irregular migration flows, while also calling on the bloc to adopt new common rules for asylum seekers.
Turkey has become one of the main corridors for migrants seeking to enter Europe, but a 2016 agreement with the European Union had reduced the numbers using the route.
"This is a situation they cannot endure any longer"
At least one person, a woman, was killed when a fire broke out at a container inside the crowded refugee camp. More than a dozen others were hurt as clashes later broke out between refugees and emergency services. The cause of the fire is yet unknown.
The events prompted further calls from NGOs, including International Rescue Committee (IRC) and Médecins Sans Frontières (MSF), for government action.
Marco Sandrone, Project Coordinator for MSF in Lesbos, told Euronews the fire was the "ultimate result of the insane and inhumane policy of the EU-Turkey deal".
"We need to call on all the Greek authorities and EU to evacuate the most vulnerable people immediately to safe accommodation on the mainland," he said. "If not possible, this evacuation needs to happen to other European countries where proper medical care can be provided."
Franziska Grillmeier, a journalist based on the island of Lesbos, told Euronews that the refugees are "still disorientated" after Sunday's fire.
"This is all about the whole feeling of insecurity here, the enormous tension and immense psychological terror people are under. This is a situation they cannot endure any longer and they are demanding safety."