Georgian police have arrested a top opposition leader and used tear gas in a violent raid on his party headquarters, further deepening a political crisis sparked by last year's disputed parliamentary elections.

Live television footage on Tuesday showed Nika Melia, the leader of the United National Movement, the country's main opposition party, being dragged from his party headquarters to be placed in pre-trial detention.

Meanwhile, hundreds of riot police used tear gas against his supporters and the leaders of all of the country's opposition parties, who have been camped out in the building since Wednesday, the Mtavari TV live pictures showed.

Scores of opposition supporters were detained.

"Shocked by the scenes at UNM headquarters this morning," British ambassador Mark Clayton wrote on Twitter. 

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Political crisis

Georgia has been in the grip of a political crisis since last October's parliamentary elections, which opposition parties have denounced as rigged.

On Thursday, Prime Minister Giorgi Gakharia resigned over ruling party Georgian Dream's plans to arrest Melia.

News of the plan sparked outrage among the opposition and warnings from the ex-Soviet country's Western allies.

In the wake of Gakharia's resignation, the opposition called for snap parliamentary polls.

Last week, the United States and the European Union called on Georgia's government to resolve the crisis peacefully and to ensure its judicial system stays free of political bias.

Melia has dismissed the charges laid against him of "organising mass violence" during anti-government protests in 2019 as politically motivated.

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