Google suffered another blow to its business in China as China's leading web portal Sina stopped using its search technology on its site in favor of a proprietary engine.

Sina Corp., owner of China's third most-visited website replaced Google's service with internally developed search technology after its contract with the search engine giant expired earlier this month, Liu Qi, a spokesman for the Chinese company, said.

The move comes a year after Google shifted its Chinese service offshore to avoid local censorship rules.

Sina CEO Cao Guowei first hinted at plans to drop Google and develop its own search technology in a teleconference last August.

Google spokeswoman Jennie Johnson declined to comment on Sina's move.

"We cannot comment on a particular partner," Johnson said. "But just as we announced last year, we will not provide censored search results to our Chinese partners."

Google's China business has encountered a series of problems since it began redirecting users to Hong Kong after its exit from China's mainland last year. Its Chinese partnerships have also suffered.

Although senior Google officials reiterated the company will never give up China, its market share in China has hit a record low as its rival Baidu cements its leadership in the country's search industry.

Google's status as global search leader is also facing challenges from players such as Facebook, Microsoft and Yahoo.

China's business press carried the story above on Wednesday. China.org.cn has not checked the stories and does not vouch for their accuracy.