The Mitsotakis government submitted a bill to Parliament on Monday to impose tighter controls on public demonstrations that frequently block traffic and turn violent.
The bill stipulates that participation in a protest rally held without police permission could be punishable by up to a year in prison.
Protest organisers may also be held liable for damage caused to public or private property during a protest.
The government argues that the changes will protect the right to protest and stop small gatherings from causing extensive disruption to traffic.
Left-wing opposition parties, including the Syriza Party, strongly criticised the plan, describing it as being reminiscent of a right-wing dictatorship in Greece between 1967 and 1974.
The Parliament is expected to vote on the bill by July 10.
A labor union backed by the Greek Communist Party said it planned to defeat the proposal with mass demonstrations.
Greece has a long tradition of public protests and several recent rallies have been held in support of the Black Lives Matter marches in the United States.
READ MORE: Greek demonstrators hurl firebombs towards US embassy in Athens [VIDEO].
