Half of Amsterdam's prostitute windows must be closed to save Europe's most tolerant city from criminal gangs and an excess of sleaze, the mayor has told The Times.

The Continent's most open red-light district, which sprawls over Amsterdam's entire historic canal district, will be reduced to two main streets under a dramatic downsizing plan drawn up by Job Cohen, the city's mayor.

Mr Cohen, who is also closing a fifth of the city's cannabis cafés and a number of sex clubs, denies that his clean-up means an end to the permissiveness that draws in thousands of tourists, many from Britain, every year.

He says that he wants Amsterdam to become better known for its art, chamber music and museums rather than as a hotspot for sex and drugs. There are currently more than 400 of the distinctive neon-lit prostitute windows from where scantily clad women beckon passers-by and about 70 “coffee shops” selling ready-rolled cannabis joints.

“The tolerance, which we in Amsterdam are proud of, is not the same as indifference,” said Mr Cohen, 61, the former Rector of Maastricht University, who resigned as the Deputy Justice Minister in Wim Kok's Labour Government to become mayor of the city in 2001.

A report drawn up for him by Karina Schaapman, a former prostitute and a member of the city council, described a police file of 80 violent pimps, of whom only three were Dutch-born. She said that more than three quarters of the city's 8,000 to 11,000 prostitutes were from Eastern Europe, Africa and Asia.

The conclusion was unavoidable for Mr Cohen — international organised criminals were taking over. “Prostitution is legalised in the Netherlands and that is OK,” the mayor said. “In the last few years we have also seen a lot of women-trafficking and women forced to be prostitutes against their will, and therefore we want to have more control.

If there is control, there is transparency. If people think they cannot do it legally so they will do it illegally, we will go after them.”

The prostitutes' union, the Red Thread, has accused Mr Cohen of using a crackdown on criminal activity as an excuse to close the windows and reverse years of tolerance. It has been drawn up at the same time as the Government is taking a tougher line on soft drugs, banning the sale of magic mushrooms and forcing the closure of all coffee shops near schools, as the Netherlands rethinks its anything-goes attitudes.

The union argues that the prostitute windows are much safer because women can deal with clients directly without having to rely on pimps.

But Mr Cohen said the research showed that pimps were still active: “It is not that we want to get rid of our red-light district. We want to reduce it. Things have become unbalanced and if we do not act we will never regain control. At the heart of this project is our desire to drive back criminality and make the city welcoming for everyone.”

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