BRUSSELS—Government workers across Belgium went on strike Thursday to protest pension cuts planned by new socialist Prime Minister Elio Di Rupo aimed at bringing the country's budget deficit in line with European Union rules and keeping the government out of the vortex of the euro-zone debt crisis.
Unions scheduled the strike for the day the Belgian Parliament debated the measures, which would raise the pension eligibility age from 60 to 62 years old and make it harder for workers in some professions to qualify for early retirement benefits, among other steps to cut long-term pension costs.
In Brussels, the bus, tram and metro systems were shut, prompting people to walk or bike to work. Some started their Christmas vacations early. Judges and magistrates protested at local court houses.
The strikes are the latest outburst of public anger against austerity reforms governments are pushing because of the economic and debt crisis. Unions in the U.K., France and other countries have held similar walkouts over public-sector pension cuts elsewhere this year. Other anti-austerity protests have turned violent in Greece.
The high-speed Eurostar and Thalys trains idled part of their service through Brussels as transport workers walked off the job. In France, a strike by airport-security personnel stretched into its seventh day, while in London, football club Arsenal postponed its Boxing Day game against Wolverhampton Wanderers by 24 hours because of a planned public-transport strike.
At the Brussels South train station, the tracks of the Eurostar and Thalys trains linking London and Paris through Brussels with Amsterdam and Germany remained empty.
"Eurostar and other onward connecting rail services will not be able to operate to or from Brussels during this period," the rail company said of the 24-hour strike.
Simply waiting a day would be tough for holiday travelers since the trains are often fully booked for days on end. All local lines were canceled on Thursday, too, keeping many workers home. "Again, it is at the expense of travelers. We are literally left out in the cold," said Kees Smilde of the TrainTramBus consumer group.
Mr. Di Rupo, appearing in parliament Thursday to defend the austerity proposals, lightly scolded the unions. "The unions have decided to protest, and it's not for the government to judge that," he said, "but strikes do not always facilitate dialogue."
Belgium's public-sector union said in a statement that the pension minister refused to include "reasonable transition measures" in the measures. "With that, he proved his contempt for the representatives of the public sector and the Belgian system of social consultation," the statement said.
The National Bank of Belgium expects the government's budget deficit to be 4.2% of gross domestic product this year. EU rules call for deficits under 3% of GDP. Mr. Di Rupo's government has pledged to bring the deficit under the 3% limit next year and to balance the budget in 2015.
Standard & Poor's downgraded Belgium last month, citing its high public debt level, slowing growth, lingering political crisis and the potential cost of supporting Dexia SA and other troubled financial institutions. Belgian 10-year bond yields rose to nearly 6%, the highest level since the start of the euro zone.
Since then, Belgium's French-speaking socialist party teamed up with five other parties to form a coalition government making Mr. Di Rupo prime minister. That appeared to calm market tensions: Belgian yields have plummeted to around 4.27%.
Belgian pensions actually tend to be less generous than pensions in other European nations, according to data from Eurostat, the EU statistics agency. Pension expenditure in 2009 was 12.1% of GDP, under the euro-zone average of 13.4% of GDP.
The typical Belgian worker's pension income is 46% of income just before retirement—the so-called "replacement ratio," an important measure of pension system finances. The replacement ratio for the euro zone as a whole is 54%.
—The Associated Press contributed to this article.
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