BEIJING: Australia and China signed a series of cooperation agreements Tuesday at the start of a visit by Prime Minister Julia Gillard intended to strengthen ties and smooth over recent spats with her country's top export market. Gillard's trip is her first to China since taking her post in June and seeks to set a new tone for relations following disputes over human rights and Chinese investment under her predecessor, current Foreign Minister Kevin Rudd. Beijing is her third and final stop on a weeklong regional outing focussing on economic ties that included visits to Japan and South Korea. China looms largest among those relationships, buying fully one-quarter of Australia's exports and providing relentless demand for Australian raw materials. Despite robust trade, ties deteriorated in 2009 after China arrested Australian executive Stern Hu of mining giant Rio Tinto, raising worries over the vulnerability of employees of foreign companies to often selective enforcement of the country's vague state secrets and corruption laws. Hu was later sentenced to 10 years in prison on charges of bribery and infringing trade secrets. The two sides also feuded over a visit to Australia that year by exiled Uighur activist Rebiya Kadeer, accused by Beijing of inciting ethnic riots in the Xinjiang region of western China in July 2009. Many Uighurs, the ethnic minority native to China's far west, have complained their rights are ignored and called for great autonomy for their region. Gillard said she raised concerns about China's human rights record, including its treatment of ethnic minorities, activists and religious groups, during talks with Chinese Premier Wen Jiabao. “He did indicate his view that China has not taken a backwards step on human rights,” she told reporters. Surveys show Australians remain dubious about Chinese investment in their economy, along with Beijing's rising military power and global influence, while Chinese officials fret about Canberra's close ties with the United States. The agreements signed Tuesday cover cooperation in trade, tourism, science and mining. No details were immediately available.