If a coach or athlete makes a “T” sign with their hands at the Olympic Games in Bejing next month, it will probably indicate their support for Tibet rather than a request for a refreshing cuppa at the finish line. With four weeks to go until the start of the first Olympics to be held in China, human rights activists are calling on competitors and spectators to show their concern for the situation in the Himalayan region by forming a “T for Tibet” with both hands.

Joanna Lumley and Jeremy Irons, the actors, are spearheading the campaign, which is launched today to refocus attention on Tibet after the issue consumed the Olympic torch relay in April, prompting a wave of violent protests along the international route.

Athletes will be encouraged to make the sign as a way of circumventing strict rules that prohibit political banners and flags inside the stadium and other Olympic venues. Anne Holmes, the acting director of the Free Tibet Campaign, said: “British and all other athletes must act as their consciences dictate. We would love to see an athlete dedicate a medal to Tibet, but we are making no demands.”

Athletes will also be guided on ways they can speak out in Beijing on Tibet without jeopardising their place at the Games. This includes voicing their concerns during press interviews after their events or wearing Free Tibet T-shirts around Tiananmen Square.

The IOC has said that athletes will be free to express their views during the Games but must not engage in any kind of “demonstration or political, religious or racial propaganda” inside accredited areas. However, there is much uncertainty surrounding the definition of propaganda.

Making the “T” sign on the podium would probably be interpreted as a political statement and could result in tough sanctions. Tommie Smith and John Carlos, the United States sprinters who won gold and bronze medals respectively, were suspended from the American team and banned from the Olympic Village for their Black Power salute on the podium at the 1968 Games in Mexico City in protest at racial oppression.

The IOC said that the focus of athletes should rest on sport, not politics. “We are aware that organisations are urging athletes to take stands on various issues,” Giselle Davies, the IOC's communications director, said. “How any result, if any, would be interpreted will come down to a commonsense approach, which the IOC will take.”