U.S. Secretary of State Hillary Clinton is voicing concern about China's aid and investment practices in Africa.

During a visit to Zambia Friday, Clinton said China's foreign assistance to Africa is not always consistent with generally accepted international norms of transparency and good governance.

She said the United States does not regard China's growing involvement in Africa as a threat to Washington, but said China's activities on the continent should be scrutinized for signs that they may not benefit the African people.

Speaking at a joint news conference Clinton, Zambian President Rupiah Banda said that Zambia has been dealing with China since before independence in 1964. He said Zambia was fortunate that China continued to buy Zambian copper during the global financial crisis.

Mr. Banda and Clinton spoke after attending a trade forum of the African Growth and Opportunity Act . The 11-year-old deal offers duty-free trade with the United States to African nations that meet good-governance and business-practice requirements.

Clinton said earlier Friday that African leaders must fight corruption if they hope to benefit from U.S. trade preferences.

Speaking to business and civic leaders in Lusaka , Clinton said the White House is committed to expanding U.S. trade with Africa.

Clinton says the Obama administration wants to develop a partnership with Africa that supports long-term progress based on economic growth, not on handouts.

Clinton next will travel to Tanzania, on Saturday, and Ethiopia, on Monday.

While in Tanzania, Clinton is scheduled to meet with President Jakaya Kikwete and discuss U.S.-Tanzanian bilateral programs.

In Ethiopia, she will hold talks with Prime Minister Meles Zenawi. She will also visit African Union headquarters in Addis Ababa to discuss regional issues with AU chairman Jean Ping.