Among prostitutes working on the street, about 80 percent come from abroad, from countries such as Romania, Bulgaria and Nigeria, via trafficking. The rest are Norwegians who tend to be substance abusers.
In recent years, street prostitution in central Oslo has become more visible, prompting calls for a ban.
But critics of the law argue it will make sex workers more vulnerable.
"The girls will have to rely more on pimps than before to get clients," Janni Wintherbauer, leader of the Organisation for the Interests of Prostitutes and a sex worker herself, told AFP.
"The pimps will organise everything: the flat where they live, the choice of clients, and how much money they get," she said.
"In the street, the girls can choose who they go with. If they don't like the look of a client, they can say no. In a flat, they can't. And the client will have paid the pimp already, whereas in the street, it's the girl who gets the money first," explained Wintherbauer.
She fears there will be more rapes and attacks on prostitutes.
"The client will think 'I've already broken the law, I've got nothing to lose.' And in a flat, a girl will be alone" where no one would be able to help her," she added.
The planned law is modelled on legislation passed in 1999 in neighbouring Sweden. There, men who buy sex face six months in jail or a fine, set in proportion to their income.
No one has yet gone to prison for the offence, but one person was fined 50,000 Swedish kronor (5,455 euros, 7,535 dollars), according to police.
"The law has been very good," said Karin Svedlund, a detective inspector at the Swedish National Criminal Police.
"It's more difficult for buyers to buy sex and it's harder for traffickers to work in Sweden," she told AFP.
Prostitutes' support groups in Sweden also appear more supportive of criminalising sex purchases than their Norwegian counterparts.
"The law has helped us in our work," said Jonas Flink, a social worker at the Prostitution Group, a help centre for sex workers in Gothenburg, Sweden's second largest city.
"We can focus solely on indoor prostitution, which covers most prostitution, whereas before all our resources were focused on street prostitution," he told AFP.
He disagrees that violence against prostitutes increases when buying sex is banned.
"It does not matter where prostitution takes place, indoors or outdoors, there will be violence in both arenas," he said, adding that he believes demand for paid sex has fallen in Sweden because clients are more afraid of getting caught.
"Men are more likely to think 'I have a family, I don't want my wife to know I went with a prostitute'," he said.
Sweden and Norway are not alone in outlawing buying sex.
Finland made it illegal in 2006 to pay for the services of a prostitute who is a victim of human trafficking. And since February 2007 kerb-crawlers in Scotland face fines of up to 1,000 pounds (1,477 euros, 2,032 dollars) and have their cars confiscated.
Source-AFP
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