Thousands of opposition supporters flooded the Albania capital Tirana on Thursday calling on the government to step down, claiming it is corrupt and has ties to organized crime.
Parliament's session was cancelled as police rolled out barbwire to protect the building.
All 65 opposition lawmakers, led by the center-right Democratic Party of Lulzim Basha, have resigned and joined protests against Prime Minister Edi Rama. The governing Socialists have 74 seats in the 140-seat parliament.
At an opposition rally on Saturday, protestors threw tones at the prime minister's office and the government headquarters and tried to break in. Police used tear gas, flash grenades and water cannon to keep protesters away.
The crisis has plunged the tiny Balkan nation into political uncertainty amid mounting concern demonstrations could morph into further violence.
"We reaffirm the right of citizens to engage in peaceful demonstrations as an essential feature and a core value of democracy, but we strongly denounce any rhetoric by political leaders calling for violence," EU foreign policy chief Federica Mogherini and Enlargement Commissioner Johannes Hahn said in a joint statement.
"Furthermore, the decision by the opposition to relinquish their mandates seriously hinders the functioning of democracy in Albania. The Parliament is the place where reforms and relevant developments should be discussed and taken forward, not boycotted," they said.
NATO member Albania is aiming to launch full EU membership negotiations this year.
cw/rt (AP, dpa)
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