Greek lawmakers have approved a set of harsh austerity measures demanded by bailout creditors to save the debt-ridden country. The vote came after a day of widespread rioting and looting in central Athens that saw buildings torched and shops vandalized.

The austerity program paves the way for Greece's European partners and the International Monetary Fund to release US$170 billion in rescue loans to stave off bankruptcy

Lawmakers voted 199-74 in favour of the cutbacks, although there was strong dissent among the two main coalition members.

The historic vote took its toll on Athens' streets. Fires caused by rioters damaged at least 45 businesses, including several downtown buildings, movie theatres, banks and a cafeteria.

Carrying flags and banners, protestors set bonfires in front of parliament, while a row of riot police tried to block crowds from surging into the government buildings.

It was the worst rioting in Athens in years.

Fifty police officers were injured and at least 55 protesters were hospitalized. Police arrested 45 suspected rioters and detained another 40.

Among some of the drastic measures approved in the austerity plan were plans to slash the minimum wage, reduce pensions and trim the ranks of civil servants.

Greek officials say the tough measures are needed to keep the country stay financially afloat and assure Greece's position in the eurozone.

The legislation also approves a bond swap deal to write off half the country's privately held debt.

Tensions escalated in Athens earlier in the day when some of the protestors attacked police with firebombs, fireworks and chunks of marble smashed from the fronts of luxury hotels and department stores. Police responded by firing tear gas into the crowd.

Athens' historic downtown, meanwhile, was strewn with rubble and terrified onlookers sought refuge in hotel lobbies and restaurants.

The violence underscores the unease many Greeks have about stringent austerity measures ordered by fellow Europeans. In order to qualify for bailout money, it must first show creditors it's prepared to undertake massive public sector reforms.

Finance Minister Evangelos Venizelos said the cuts were needed if Greece is to survive its financial crisis.

"There are very few such moments in the history of a nation," he said. "Our country has an acute issue of survival."

German Finance Minister Wolfgang Schaeuble was quoted as telling the Welt am Sonntag newspaper Sunday that Greece "cannot be a bottomless pit."

"That's why the Greeks must finally put a bottom in," he added. "Then we can put something in too."

Leftist parties and the small rightist LAOS -- a former junior coalition partner -- had vowed to vote against the new austerity measures.

"You are not trying to save Greece, but a handful of industrialists," Communist Party spokesman Thanassis Pafilis said before the vote.

"And you disgracefully blame the struggling people who created the wealth we have. You are trying to send them back to the Middle Ages. We will not allow it."