Police with truncheons pushed back a crowd of several hundred anti-government protesters during a police parade addressed by President Mikheil Saakashvili on the outskirts of the capital, Tbilisi.

Opposition leaders said three people were injured. At least one was seen bleeding from the head.

Opponents of Saakashvili are threatening to take to the streets after May 30 local elections, the first electoral test of his United National Movement since the former Soviet republic fought a five-day war with Russia in 2008.

Saakashvili is under pressure to fulfil the promise of the 2003 Rose Revolution to forge a Western-style democracy.

The election arm of the Organisation for Security and Cooperation in Europe is sending some 350 observers to the poll, which will directly elect municipal officials including the mayor of Tbilisi, where more than one million of the country's 4.5 million population live.

Critics accuse Saakashvili of marginalising the opposition, manipulating the media and arresting opposition activists.

"You see that we've clashed with the police at this rally, and we will continue our fight until we are successful and while illegal prisoners are still in prison," said Zurab Nogaideli, a former prime minister now in opposition.

The government says the Rose Revolution is a work in progress and that significant progress has been made in democratisation, tackling corruption and attracting foreign investment.

Saakashvili's allies cite opinion polls that suggest the ruling party still enjoys significant support nationwide.

Diplomats say that support is due partly to the inefficacy of the opposition, which has been unable to consolidate and present a coherent campaign.

Three months of opposition street protests last year demanding Saakashvili quit petered out with little result.

Saakashvili's support in the West has dwindled since the 2008 war, when an assault by Georgia's U.S.-trained military on the breakaway region of South Ossetia triggered a devastating Russian counter-strike.

Saakashvili regularly evokes the perceived threat from Russia. The 'Soviet empire' is like a corpse "that has started to show signs of life again," he told Thursday's parade marking Police Day.

"I'd like everyone who is itching to restore the Soviet empire ... to know that the Soviet Union is over in Georgia."

(Writing by Matt Robinson; Editing by Sonya Hepinstall)

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