Hundreds of demonstrators gathered on a central square in the Armenian capital on Monday pledging to carry on protests over energy price hikes after police cleared a key artery they had blocked for weeks.

Riot police earlier detained dozens of protesters and dismantled a barricade of dumpsters they had built across an avenue close to the presidential palace in Yerevan, an AFP journalist at the scene said.

Armenian authorities launched a criminal investigation Friday into police officers involved in a brutal crackdown on demonstrators protesting against electricity price hikes.

Mikael Aharonyan, spokesman for Armenia's special investigative service, told AFP that the inquiry had been opened into alleged police violence, abuse of power and obstructing journalists.

Armenian authorities threatened Sunday to forcefully break up a protest against rising electricity prices and police brutality after the president announced concessions in a bid to calm tensions.

Thousands of demonstrators were expected to take to the streets of the capital Yerevan in the evening after President Serzh Sarkisian's promise that the government would shoulder the burden of a controversial hike in electricity prices failed to appease the activists.

The Armenian government on Thursday refused to reverse a controversial electricity price hike, sparking fresh anger among thousands of demonstrators who have rallied in the capital for a week.

Under pouring rain, some 7,000 protesters rallied Thursday evening near the presidential palace after Prime Minister Hovik Abrahamyan said his government would proceed with raising power tariffs despite anger in a country already hard hit by the economic crisis in Russia.

Hundreds of demonstrators in the Armenian capital ignored police calls to disperse on Wednesday, digging in for a new day of protests against electricity price hikes and police violence.

Braving sweltering heat in Yerevan, some 600 protesters -- mainly young people -- vowed to keep up the pressure on President Serzh Sarkisian's government until it reverses a decision to raise electricity tariffs for households.

President Vladimir Putin on Friday called on French leader Francois Hollande to restore ties after a year of tensions over Ukraine as the two leaders met on the sidelines of genocide commemorations in Armenia.

"Unfortunately, our ties are not in the best shape, trade turnover is falling including with France which only causes regret," Putin told Hollande in the Armenian capital Yerevan.

The leaders of France and Russia on Friday joined ceremonies marking the centenary of the massacre of some 1.5 million Armenians by Ottoman forces, a hugely emotional event that remains a diplomatic minefield.

During a commemoration at a hilltop memorial in the Armenian capital Yerevan, French President Francois Hollande urged modern day Turkey to end its refusal to recognize the massacre as genocide, saying he bowed in memory of the victims.

Maronite Patriarch Beshara al-Rahi has urged the international community to recognize the Armenian genocide, expressing fears of further such atrocities against Christians in the world.

Al-Rahi, who is in Armenia to attend the ceremony to mark the centenary of the World War I killings by Ottoman Turks, was quoted by the National News Agency as saying on Thursday that “the international community and people with goodwill should recognize the genocide.”

Mass killings? Mutual bloodletting? Genocide? The hundreds of thousands of dead have been silent for a century, but generations on, Armenians are still battling to get the World War I slaying of their ancestors recognized as a genocide.

As Armenians around the world gear up to mark 100 years since the start of the slaughter on April 24, the struggle to get the world -- and above all Turkey -- to use the term "genocide" remains deeply divisive.  

Armenian President Serzh Sarkisian on Monday threatened arch-foe Azerbaijan with an "asymmetrical" response to any attempt to use military means in resolving their long-standing conflict over the disputed Nagorny Karabakh region.

"Until now we were reacting symmetrically ... from now on we could take asymmetrical actions," Sarkisian told a televised meeting with Armenia's defense ministry.