China has taken the unprecedented step of setting aside three sites for demonstrations during the Olympics, but it has imposed strict rules that could make any protest impossible.

The move follows months of internal debate on what to do about foreign visitors to the Games who are eager to exercise freedoms to which they are accustomed in many other countries without allowing Chinese to take to the streets.

The compromise to designate three parks for approved protests enables Beijing to show the world it can be tolerant of open debate while preventing its people from seeing any demonstrations.

The three parks in corners of Beijing near some of the most distant stadiums are screened off by fences or trees that ensure passers-by will not see any demonstrations - if any are approved.

Spontaneous demonstrations will not be allowed. Chinese law stipulates that would-be demonstrators must apply for permission five days in advance, detail the nature of the protest and the number of people expected to take part. That means that approved demonstrations almost never take place in China, although thousands of “mass incidents” by protesters ranging from peasants deprived of their land to pensioners demanding higher benefits occur every year.

Officials were vague about how groups would go about the process of winning approval for a protest during the Olympics. Host cities have in the past designated specific “protest pens” because the International Olympic Committee charter bans demonstrations or political, religious or racial propaganda at Olympic venues or sites.

An official at Ritan Park, one of the three designated areas, refused to comment, saying that the police were in charge. Organisers of the London games had planned to set up a base in the park, one of the prettiest and greenest in Beijing, to showcase the city that will host the next Olympics in 2012 but they were asked to leave a few weeks ago because the park of the Altar of the Sun was needed for security purposes. The London Development Agency was offered an alternative location near one of the city’s old lakes.