Rebiya Kadeer should not be commenting on the Rio Tinto case because she is unaware of the facts and only using the issue to further her political ambitions, an expert said.

Kadeer, the head of the World Uygur Congress, was earlier accused by the Chinese government of stoking last month's riot in Urumqi, the capital of the Xinjiang Uygur autonomous region, that left at least 197 dead and 1,600 injured.

Despite China's objections, Kadeer, who now lives in the US, yesterday made a televised address from the National Press Club in Canberra and urged Australia to use its muscle in the resource sector to push for the release of Rio Tinto executive Stern Hu.