SYDNEY (AFP) - Australian athletes competing at the Beijing Olympics will be allowed to voice their opinions on human rights, Tibet and other contentious issues, but are banned from making public political displays.

Human rights in China is a sensitive issue in the leadup to the August Games and the Olympic torch relay has been repeatedly disrupted by groups trying to highlight grievances against China's communist rulers, including the treatment of dissidents and a security clampdown in Tibet.

The International Olympic Committee (IOC) only recently reminded China to draw a line between sports and politics, after a Communist party official lashed out at independence sentiment in Tibet during the Olympic flame relay in the region, which China annexed in 1951.

Activists have urged athletes competing in the Games to speak out on matters including Beijing's control of Tibet, its policies on the Sudanese region of Darfur and human rights.

The Australian Olympic Committee (AOC) has given its Beijing-bound athletes carte blanche to express their opinions, including on human rights and other issues, but political protests in Games venues remain forbidden.

"While they are allowed to express a point of view on any issue, we wouldn't allow them to wear 'Free Tibet' shirts, or unfurl banners inside venues or things like that," an AOC spokesman said.

Pressure on some other national Olympic associations forced them to lift gagging orders on their athletes.

British athletes were originally told they could not comment on politically sensitive issues at the Games before the edict was retracted by British Olympic chiefs accused of gagging free speech.

New Zealand Olympic officials also lifted a controversial gagging order on its athletes following political pressure.

The IOC has agreed to allow Games athletes to have on-line diaries or blogs, but has imposed strict limits on how they may be used.

IOC President Jacques Rogge said that his organisation had a long-standing rule that "no kind of demonstration or political, religious or racial propaganda is permitted in any Olympic sites, venues or areas."

The measure is in place to prohibit any repeat of actions such as the black-gloved protest US sprinters Tommie Smith and John Carlos made on the podium at the 1968 Mexico City Olympics.

AOC President John Coates said the AOC respects the right of its athletes to have an opinion in Beijing as long as they conform to the IOC guidelines.

"We're not going to gag our athletes in any way and I'm certainly not going to sit up at night and read 476 blogs," Coates said. "We respect the right of our athletes to have an opinion and to express it.

"They'll be told what the guidelines are from the IOC. The Olympic charter says that you can't participate in political demonstrations. I don't think expressing an opinion on something amounts to a demonstration."

Coates said issues could be raised at mixed zones, in press conferences and media interviews, and in internet blogs at the Beijing Games, but "we rely on the common sense of athletes in showing respect for the dignity of fellow athletes, including those of the host country".

The actions of Australian road cyclist and likely Beijing participant Cadel Evans, who wore a "Free Tibet" T-shirt in a Belgian road race this year, is one such protest that will be outlawed in Beijing.