Paris, France (CNN) -- The lower house of the French parliament approved a controversial pension reform bill Wednesday, despite weeks of protests that brought millions of demonstrators into the streets to try to stop it.
The National Assembly vote of 336 to 233, with five abstaining, was the last legislative hurdle facing the measure.
French unions declared nationwide strikes to try to stop the bill, which raises the retirement age from 60 to 62, and workers and students poured out onto the streets repeatedly over the past two months to protest.
The French Senate gave its final approval to the bill Tuesday, passing it 177-151 despite the protests.
Unions are making a last-ditch effort to derail the measure, calling for nationwide strikes Thursday and again next week.
The Paris demonstration is scheduled to start at 1 p.m. local time, and flight cancellations are expected out of Paris airports. The Paris metro is expected to run normally, or nearly so.
Lawmakers can still force the bill to go to the Constitutional Council before it becomes law. It takes 60 legislators to do that. The opposition Socialist party has said it will try that route. If the law ends up in front of the council, the body has eight days to decide whether it is consistent with the Constitution.
Once that happens -- or if lawmakers do not require the council to consider it -- the bill becomes law when President Nicolas Sarkozy signs it. He said he will not do that before November 15, but has been one of the law's strongest backers.
The government said the reform is necessary because the current pension system is unaffordable.
Demonstrations took place Tuesday at four universities around the country, the Ministry of Education said. Most universities are on vacation this week.
The country's finance minister said earlier this week she doesn't expect ongoing strikes to cause a significant blow to France's growth forecast for this year.
"There are no winners and no losers in this affair. What is important is to take responsibility, to realize that the economy needs to keep going," Finance Minister Christine Lagarde told French radio station Radio Classique on Tuesday. "I do not deny that we've had several days where there has clearly been an economic impact. I don't think it's enough to change our growth forecast for the entire year."
A spokesman for the Ministry of Finance said France's expected increase in gross domestic product for 2010 is 1.6 percent, a level that has held steady since August.
French workers staged a series of rolling strikes and demonstrations this month and in September.
Lagarde has said the country cannot continue to pay its debts -- to retirees and others -- by borrowing at current levels. The government has announced it will try to cut the deficit from 8 percent to 6 percent of GDP by next year, an ambitious goal.
Six major French unions have called for further nationwide demonstrations on Thursday and November 6, saying that protests so far show the people are ready to dig in for the long haul.
CNN's Winnie Andrews and Jim Bittermann contributed to this report.