The Greek Parliament voted through the ruling coalition's latest package of including pension cuts and income tax hikes, amid clashes late Sunday on nearby Athens streets between police and rioters opposed to the austerity measures.
Prime Minister Alexis Tsipras argued that the pension system "can not survive without far-reaching reform." All 153 members of his left-right coalition in the 300-seat chamber voted for the package, in a bid to receive more bailout money from the country's international creditors.
Eurozone finance ministers are to meet Monday to discuss negotiations with economically battered Greece.
The legislation is meant to net 3.6 billion euros toward debt reduction, a condition demanded by international creditors for the country to receive its next aid tranche, with another 1.8 billion euros of indirect tax hikes to be voted on in the coming weeks.
While lawmakers were debating the legislation, hundreds of rioters had plunged a peaceful demonstration in front of parliament into chaos.
Some assailants hurled Molotov cocktails and other objects at police. Broadcast video showed police responding with teargas, with acrid smoke spreading across Syntagma Square near parliament.
Through the day, thousands of people gathered in front of parliament to protest retirement benefit cuts and tax increases. One protester told Greek television that the legislation is "the gravestone of the retirement system as we know it."
Police estimated that 20,000 people participated in peaceful protests, but many demonstrators fled when the clashes erupted. Calm was later restored.
After two days of debate, no opposition legislators supported the measure.
Kyriakos Mitsotakis, head of leading opposition party Nea Dimokratia (ND), called for the resignation of Tsipras, whom he accused of wasting time through pointless negotiations with Greece's creditors, causing delays that only increased the necessary cuts.
He accused the prime minister of breaking his campaign promises not to cut pensions or raise taxes. In Sunday's debate, Nea Dimokratia said the government was choosing to slash pensions while refusing to shrink the government.
Inside parliament, a confrontation between cabinet members and the far-right Golden Dawn party led to a 40-minute delay in the debate.
Athens and its international creditors have struggled for months to agree on structural reforms and budget-cutting measures that would allow the cash-strapped government to continue receiving bailout aid. Concerns are growing that Greece is once again nearing bankruptcy.
European Commission President Jean-Claude Juncker said ahead of the finance ministers' meeting that he thinks Greece is on a good path.
"We're currently doing the first check of the programme, and the targets are as good as reached," he was quoted as saying in newspapers belonging to German publisher Funke Mediengruppe.
At Monday's meeting, finance ministers will "hold first discussions about how Greece's debt can become sustainable again," he said.
The parliamentary vote was brought forward from Wednesday to strengthen the hand of Greek Finance Minister Euclid Tsakalotos in Monday's talks, according to government sources in Athens.
The austerity measures are a condition for Greece to receive a third aid package from international creditors, which has a volume of up to 86 billion euros.
The International Monetary Fund, one of the international creditors, has additionally urged eurozone governments to enter debt relief negotiations with Greece.