PRETORIA, March 31 (Xinhua) -- China on Wednesday pledged to import more value-added products from South Africa to optimize bilateral trade.

"China will continue to take measures to expand imports from South Africa, particularly those value-added products so as to increasingly optimize bilateral trade mix," top Chinese political advisor Jia Qinglin told a business forum on Wednesday.

Jia, chairman of the National Committee of the Chinese People's Political Consultative Conference (CPPCC), the country's top advisory body, delivered a key-note speech at the one-day China-South Africa Economic and Trade Forum in Pretoria.

China has become South Africa's biggest trade partner and exporter as bilateral trade volume hit a historic high of more than 16 billion U.S. dollars in 2009, which was over ten times than that in 1998 when the two countries forged diplomatic ties, Jia said.

South Africa is China's second biggest trade partner in Africa with bilateral trade volume accounting for nearly 20 percent of China's trade with the African continent, according to Chinese Customs.

The two countries has generally maintained a trade balance as China exported machinery and durable goods to South Africa, which exported a great amount of minerals, diamond, grape wine and crafts to China, Jia said.

"The two countries should deepen two-way investment," Jia said, citing South Africa's expertise in energy development, mineral exploration and manufacturing and China's advantages in textile, garment, electronics, telecommunications and processing.

Jia called for both countries to work closely in greenhouse emissions cut, new energy, forestry, finance and logistics, among others.

"China will encourage businesses with strong capacity and good credit to expand investment in South Africa's manufacturing so as to transfer technology, train staff and spur employment," Jia said.

Jia proposed both governments play a better role in facilitating bilateral trade, including supervising implementation of trade deals and improving work efficiency.

South Africa was the last leg of Jia's ten-day African tour which already took him to Cameroon and Namibia. Jia had met with South African President Jacob Zuma and held talks with Mninwa Mahlangu, chairman of the National Council of Provinces of South Africa.

Jia will leave Pretoria Thursday morning to conclude his African trip.