Revenue from the ads run into tens of thousands of pounds, but despite a recent 19pc year-on-year fall in classified ad revenue the US-owned group has decided to remove all them from its newspapers and websites with immediate effect.

The decision came to light in two stories published in the Croydon Guardian and the Richmond and Twickenham Times, part of Newsquest's South London division.

Andy Parkes, group editor at Newsquest South London, said: "Despite operating in accordance with industry guidelines, the company has taken a decision to no longer publish adult services advertisements, either in print or on its websites.

"Increasing concerns regarding the appalling issue of human trafficking has been significant in this decision, which is effective immediately," he added.

Campaigners against so-called "sex slavery" and people trafficking have welcomed the move, which is also taking effect on other Newsquest-owned newspapers across the country.

A Croydon Community Against Trafficking spokesman said: "After thousands of letters and the shouts of a loud and concerned community, Newsquest and their local papers have responded in a brilliant way."

A spokesman for the Salvation Army, which has also worked to reduce sex trafficking, added: "The link between these adverts and the supply of trafficked women to meet these demands has been well documented, and we would like to see other publications now following this example."

Recent figures revealed that Newsquest, a subsidiary of US firm the Gannett Corporation, suffered a 19pc year-on-year drop in classified advertising revenue last month.

The fall in revenue stemmed from a 36.8pc decline in property ads, a fall of 17.3pc in employment ads and 14.9pc in automotive ads across its British titles, compared with the previous June

The media pundit and blogger Roy Greenslade commented: "I must salute Newsquest for having decided to forgo the income from adult services adverts in its regional and local newspapers.

"Given the financial difficulties facing the group - the depth of which emerged in the latest results from its US parent, Gannett - it is even more praiseworthy," he added.