City officials have closed a migrant reception area overlooking the Milan train station's main entrance hall where hundreds have been sleeping this week amid increasing health and sanitation concerns.

Mayor Giuliano Pisapia told reporters at the station on Saturday that progress has been made, saying "You can see that at the Central Station there is no more degradation."

The head of the Progetto Arca charity said the mezzanine area was closed overnight after new centers were opened, but that about 150 migrants slept outside the station.

Hundreds of migrants, mostly Eritreans arriving from southern Italy after being rescued at sea, have been sleeping in and around the station recently because of a lack of beds in city-organized centers.