A group of Kenyan prostitutes has claimed they are being driven out of business by stricter night-out rules that have been imposed on British soldiers deployed in the country, following a series of incidents.

British officers were the main source of income for prostitutes in in the town of Nanyuki, in the Rift Valley, about 200km north of Nairobi, according to the leader of a local unofficial sex workers' union.

"For normal sex the British pay you 4,000Ksh [£30], but the Kenyans pay 200Ksh or 300Ksh," sex workers' representative Margaret Wambui told The Times.

"Kenyan people take a long time but the British only take a few seconds, so you can go and find another customer."

Nanyuki hosts a British army base used to train troops before deployment in Afghanistan.

A few months ago, however, British authorities at the base clamped down on soldiers' downtime, allowing them out of the base only under strict surveillance.

Officially implemented because of a jurisdictional dispute with the Kenyan Government, the new regime caused a dip in prostitutes' income.

However Wambui said the change is due to a series of incidents involving British troops in the city and called for authorities to relax the restrictions.

In August 2012, two UK soldiers were accused of involvement in the killing of a prostitute, whose body was found in a septic tank in a hotel in town a couple of months after she disappeared.

Agnes Wanjiru-Wanjiku, 21, was reportedly last seen entertaining the two Brits in a bar.

A few months earlier, more than 200 soldiers were involved in a drunken brawl at the local Sportsman's Arms bar.