(CNN) -- French lawmakers voted Wednesday in favor of making it an offense to pay for sex, a move toward criminalizing use of prostitutes.
The bill passed the National Assembly, or lower house, by 268 votes to 138, with 79 abstaining.
It must pass the Senate and be signed by the president before it becomes law, a process that could take several months.
Prostitution is currently legal in France for both the prostitute and the client.
The measure would impose fines of at least 1,500 euros (about $2,000) on people caught paying for sex.
The divisive proposal has sparked public demonstrations both for and against, according to CNN affiliate BFM-TV.
The vast majority of lawmakers from the governing Socialist Party were expected to vote in favor, with some exceptions. The majority of the opposition center-right UMP is against the measure, as is the Green Party.
Socialist lawmaker and former minister Jean Glavany wrote on his blog that he would vote "with my head, but without enthusiasm."
He said he was backing the law on two grounds: "on the one hand, the fight against mafia and pimping, on the other hand, social protection and help for prostitutes to reintegrate."
According to the draft bill, research suggests that there are about 20,000 prostitutes in France, of whom 85% are women. At the same time, 99% of the clients are men.
France witnessed a historic shift between 1990 and 2000, it says, in which the proportion of foreign-born prostitutes jumped from 10% to close to 90%.
The countries of origin are principally Romania, Bulgaria, Nigeria and China, it says, showing the "growing influence of trafficking networks on prostitution."