The leading medical adviser to the Olympic Games has called on the organisers of London 2012 to toughen their stance on drug cheats by pressing the Government to make doping a criminal offence.

Lord Sebastian Coe, chairman of the London 2012 organising committee, insists on a zero-tolerance policy towards performance-enhancing substances, but fears are being raised that the Games starting five years on Friday will be soft on drugs.

Professor Arne Ljungqvist, the chairman of the medical commission of the IOC, has urged Coe that, unless legislative changes are made, London 2012 will be a significantly simpler Games for dope cheats to prevail in than other Olympics before it. “Doping is unacceptable, a social crime,” Ljungqvist told The Times. “A coming host of an Olympic Games should show a good example here.”

Ljungqvist’s concerns are echoed in the House of Commons by Phil Willis, MP, the chairman of the all-party Science and Technology Committee, whose report into illegal performance enhancement in sport, published on February 7, criticised an “apparent complacency” in gearing up for policing antidoping at London 2012.

Willis has told The Times that “an element of complacency continues”, his criticism directed particularly at UK Sport, the agency responsible for antidoping. “UK Sport will be pilloried if we have an enhancement-tainted Games,” he said. “Our argument is that we have an opportunity not just to stage the Games but to influence the agenda for sport in a significant way.”

Ljungqvist’s fears are best illustrated by the astonishing drugs bust on three billets occupied by members of the Austria team that was under the direction of Walter Mayer at the Winter Olympics in Turin last year. A full-scale doping laboratory was discovered on site, including six blood bags, 18 used syringes, 18 packs of unused syringes, 12 packs of syringe needles and 79 devices for haemoglobin testing. Unless UK legislation is changed, it is unlikely that such an operation at London 2012 would be uncovered.

In Italy, possession of doping substances is a crime, so the police were able to conduct the raid. In the UK, they would not.

On November 29 last year, Ljungqvist appeared at the House of Commons in front of the Science and Technology Committee and urged Britain to match other European countries that legislate against possession. He then spoke to Coe on the subject at an IAAF Council meeting in March and says that he will take up the campaign within the World Anti-Doping Agency, of which he is vice-president.

“The coming Olympic hosts should show a good example,” particularly a country like Britain,” Ljungqvist said. He is also hoping for a more receptive ear from Gerry Sutcliffe, the new Sports Minister, because “I noticed that Richard Caborn [the former Sports Minister] did not understand what I said on this”.

His best ally may yet turn out to be the British Olympic Association (BOA), which today will launch its own Anti-Doping Commission, which he will be advising. One of the commission’s terms of reference will be the evaluation of the advantages and disadvantages of introducing legislation on doping. However, the BOA is powerless to push legislation through Government.

The BOA’s commission will also analyse another vexing issue on doping in sport in the UK by asking whether the responsibility for antidoping should be stripped from UK Sport and handed to an independent agency. Because UK Sport is the funding agency for many of the UK’s elite sportspeople, it is considered by many to be a conflict of interests for the body to be policing them.

This was an argument resisted by Caborn. However, in the cause of promoting a London Olympics that is as clean as possible, his is a stance that soon may be no longer tenable.