A DEEP green Vauxhall Astra pulls up outside the Vernon Arms public house in the Mapperley district of Nottingham. Two scruffy-looking kids get out and head for the ladies' toilet inside the pub. They lock the door and, crouching on the toilet seat, inhale the white powder nestling in a scrunched- up piece of paper until their eyes begin to stream.

Trish and Jenny have both just turned 17. They were in the same class at school. They wear tatty anorak tops; Jenny wears jeans and Trish a pair of loose tracksuit bottoms. They go everywhere together, clinging to each other in the chilly Nottingham night air as they search for punters who will provide them with the cash to buy their drugs.

Trish and Jenny are a new phenomenon on Nottingham's streets: young prostitutes whose primary need is not to feed their children or pay the rent but to satisfy an addiction to cocaine. They offer cut-price sex, with or without condoms, to anyone with money - and they don't think twice about robbing the clients.

Not only are they giving the Nottinghamshire Constabulary's Vice Squad extra cause for concern because of their age and drug habits, but they are seriously irritating the older, more traditional prostitutes, who feel they are being undercut by unfair competition.

Jenny is tiny - five foot nothing, and at first glance you would not guess that she is any older than 13. She has had three punters already and it is only just after eight in the evening. She will do at least a couple more before she goes back home to her mum, who thinks she is out with friends. She has no condoms on her.

Jenny is undercutting women like Denise and Sabrina, 'older' prostitutes who have been working the beat for years. Denise, 28, has three children and lives in a well-furnished council house with all mod cons: television, video and washing machine. She makes up for the shortcomings of a social security income through prostitution. 'I generally aim to make around pounds 90 to pounds 100 each night, and I come out about three nights a week. I budget on about pounds 20 a day for the kids' food and clothes and the rest I save. I want to buy a new car.'

Although Nottingham's prostitutes do not work in a co- operative, Denise and the other 'older' prostitutes all charge the same rate: pounds 20 in the client's car, pounds 25 inside a flat. 'The first I knew that something had changed was when a punter pulled up and asked me my price. When I said pounds 20 he said a little girl up the road had offered pounds 10. He also said she would do it for pounds 40 without a condom and I told him if he wanted to be stupid he could.'

Denise and Sabrina work on Southey Street, down a steep hill from the Vernon Arms. Sabrina, who is 36, has kicked one of the 'little 'uns' off her patch - literally, with a sharp patent leather stiletto boot. Denise has not had to resort to physical violence. 'I tell them to piss off and they usually do, they know they can't come down here, this street is off bounds to them.'

The generational divide between Nottingham's prostitutes is distinct and tensions between the two groups can run high. Earlier this year, two of the younger girls, working in a pair, blackmailed a 'punter' for pounds 200 by threatening to report his car number to the police. The older women are furious.

'You don't rob punters like that, it only creates aggro for the rest of us. If you want to rob a punter, you wait until he goes out of the room and take a few fivers from his wallet. That way, he never knows and there's no harm done. We've all done it, but you don't frighten them off or make them angry,' says Theresa, who at 31 says she is nearly 'past it'.

Sabrina, a beautiful black woman who wears an auburn bobbed wig, skin-tight leather skirt and gold chains, thinks the younger girls' antics are the cause of a recent spate of baseball-bat attacks on Nottingham's prostitutes. 'We all know the rules of this game, we need them and they need us. If you piss them off, there's going to be trouble,' she says. 'The rules are, we all charge the same, we stick to our own patches, we don't blackmail punters and we insist on condoms.'

She could have added: 'And we dress the part.' In Nottingham, the easiest way to guess a prostitute's age is by the way she dresses. The older women wear mini-skirts or leather trousers, thigh-length boots, plunging necklines and wigs. The younger ones could be any other teenager in their jeans and track shoes. Only the way they hang around gives them away. If you're a woman and you stand around in Mapperley, you will be asked how much you charge within five minutes.

Like many of the younger girls, Jenny first got hooked on cocaine during one of a series of sojourns inside a children's home, periods when her mum, single and looking after four children, simply could not cope. In that twilight age, at 16 and 17, when state benefits are scarce, prostitution, she says, is the only way she can earn money to fund her habit.

While the older prostitutes freely admit to smoking the odd cannabis joint, they say they do not take hard drugs. The story is the same in other British cities. In Bradford, the line between the older and younger prostitutes is clearly defined: north of Marlborough Road, in Church Street, the young ones have free rein. South, in Lumb Lane and near the Bradford Working Women's Project, offering tea and condoms at all hours of the night, the older women guard their territory jealously.

Sally, in her thirties, speaks with vitriol about the time she attacked a teenager trying to steal her patch. The Bradford Working Women's Project is trying to settle differences between the age groups, and to try and encourage the younger girls to come to the drop-in, where they can receive free condoms and sex education. But while there is tension between the groups, the younger ones prefer to stay away.

'They're just jealous because we're younger than them,' says Jenny, 'and they know the punters prefer us, and we're cheaper.' The words sound brave, but she looks frightened and clings to Trish's arm. Every time a car sweeps past her, she jumps. One pulls up and stops just ahead. She and Trish walk over to the driver's window and peer in. A few seconds later they jump in the back and the car heads in the direction of the Victoria Centre car park, a shopping centre in the middle of Nottingham. Trish and Jenny have told the man they are both 15. They charge pounds 10 each.

Back down the hill in Southey Street, Denise is having a quiet night. She blames market forces. Naturally the punters prefer the younger girls - they are cheaper and do more than just straight sex. Just then one of her regulars, driving a red Ford Escort, stops at her corner. Denise smiles broadly and jumps into the passenger seat.

The local outreach organisation POW - Prostitute Outreach Workers - is trying to counteract health problems associated with prostitution by offering free condoms. Not only are they available at the nearby drop-in on Alfreton Road, but workers will regularly walk through the red light district distributing them. Their advice and free condoms do not seem to help Trish and Jenny, who either do not know about or do not care about sexually transmitted diseases.

Nottingham's red light district is unusual in that there are few, if any, pimps in the area. There are one or two drug dealers and a few boyfriends who come to look after their girlfriends' money, but it is not a threatening place. Part of the district is rather smart middle class suburbia - well-built solid Victorian terraces, sweeping stretches of green parkland and off-street parking. The residents are fed up with this highly visible problem. Only recently, Nottingham police conducted a vice blitz, getting tough on both the kerb crawlers and the prostitutes. On the first day of the initiative one of the officers posing as a client was approached by a 13-year- old girl. Even for a hardened vice squad officer, it was an unsettling experience.

Sergeant Jeff Haywood, of the Nottinghamshire Constabulary, said: 'We do get the older ones complaining about what the younger ones get up to. There is some truth in what they are saying - undercutting them and the like - but in the end, they are just businesswomen concerned with anti- competitive practices.'

Sabrina does not think it should be like this, however. 'Our lives are hard enough as it is without having tearaways, who in the end go back to their families every night, turning the punters against us and spreading disease.'

(Photograph omitted)