Protesters and police skirmished in Georgia's capital for a fourth straight night on Sunday, with signs that opposition was spreading across the country to the government's decision to suspend talks on joining the European Union.

Tensions have been rising for months in the country of 3.7 million people between the ruling Georgian Dream party and opponents who accuse it of pursuing increasingly authoritarian, anti-Western and pro-Russian policies.

The crisis has deepened since Thursday's announcement that the government would freeze EU talks for four years, with thousands of pro-EU demonstrators facing off against police armed with tear gas and water cannon.

Protesters gathered again in Tbilisi on Sunday night on central Rustaveli Avenue, tossing fireworks at police, who responded with volleys of water cannon.

Well after midnight, after hours of standoff, police began moving demonstrators away from the parliament building and down Rustaveli Avenue towards the Tbilisi opera house and began erecting barricades with whatever materials they could find.

"Quite frankly, it's been very tiring to see that our government does not hear what the people desire," said protester Nikoloz Miruashvili.

"I'm here for a very simple reason, to defend my European future and the democracy of my country."

Four opposition groups urged protesters to demand paid leave from their jobs under the labour code to attend protests and asked employers to provide the time off.

Georgia's pro-Western President Salome Zourabichvili called for pressure to be brought on the Constitutional Court to annul elections last month won by Georgian Dream. Both the opposition and Zourabichvili say the poll was rigged.

Beyond the capital, Georgian news agency Interpress said demonstrators had blocked an access road into the country's main commercial port in the Black Sea city of Poti.

Georgian media reported protests in at least eight cities and towns. Opposition TV channel Formula showed footage of people in Khashuri, a town of 20,000 in central Georgia, throwing eggs at the local Georgian Dream office.

The EU and the United States are alarmed by what they see as Georgia's shift away from a pro-Western path and back towards Russia's orbit. Georgian Dream says it is acting to defend the country's sovereignty against outside interference.