Athens - Greek labour unions were preparing to take to the streets of Athens Sunday ahead of a midnight budget vote by lawmakers.
Workers are opposed to the government's plans to continue pushing through harsh austerity measures, including tax hikes, as well as salary and pension cuts.
The 2015 budget, which has not met the approval of the country's international lenders, foresees an economic growth rate of 2.9% and unemployment falling from 24.8% to 22.6%.
Athens also says it will achieve a primary budget surplus of €3.3bn, or 3% of gross domestic product (GDP) next year, which is in line with international bailout estimates.
It also estimates that the budget deficit will be €338 million euros or 0.2% of GDP next year. Creditors, however, insist it will be closer to 3% and demand a new austerity drive.
But the unpopular coalition government is keen to avoid such measures in order to ward off snap elections next year.
Opinion polls show the far-left anti-bailout Syriza party ahead of the conservative-led coalition and would most likely win if elections were held in the immediate future.
Greece's public service union, Adedy, said the "budget would lead Greeks into greater deprivation and would increase poverty," in a written statement ahead of Sunday's rallies.
Despite surpassing its budget targets, negotiations between the government and creditors - made up of the European Commission, the European Central Bank and the International Monetary Fund, collectively known as the troika - remain deadlocked.
Aside from the projected size of the budget gap, both sides also remain at odds over pension and labour market reforms.