By Harry Papachristou and Karolina Tagaris
ATHENS (Reuters) - Greece's coalition government on Wednesday passed an austerity 2012 budget aimed at shrinking its debt mountain with tax hikes and spending cuts, hours after protesters clashed with police outside parliament.
Three major parties backing technocrat Prime Minister Lucas Papademos solidly voted for the budget plan, a package of deeply unpopular measures needed to cut the deficit and show foreign lenders the country is sorting out its finances.
"Successful implementation of this budget will restore the country's international credibility and create the conditions to rescue the economy," Papademos told lawmakers. "We can't afford to keep whining...the targets are ambitious but feasible."
But one of the leaders, conservative party leader Antonis Samaras, made clear his support was solely aimed at rescuing Greece from immediate default and vowed to soften tax steps and boost growth measures if he wins power in elections expected in February.
"Our disagreements remain... we are approving the budget because it is an absolute priority to safeguard the viability of Greek debt," said Samaras, whose New Democracy party is the front-runner to win the next election but fall short of an absolute majority.
Samaras, who has long opposed the EU/IMF austerity policies imposed by his Socialist rival, former prime minister George Papandreou, under a 110-billion euro bailout agreed in 2010, made clear he will insist on snap elections in February, after Athens clinches a bond swap deal to cut the country's debt.
As lawmakers debated the budget, hundreds of masked youths hurled petrol bombs and clashed with Greek police outside parliament when protesters marched to mark the police shooting of a student in 2008, which led to the worst riots in decades and helped topple the then conservative government.
(Additional reporting by Renee Maltezou; Editing by Angus MacSwan)