China's privately held Dalian Wanda Group is set to launch a 5 billion yuan ($813 million) e-commerce joint venture with domestic Internet giants Tencent Holdings Ltd and Baidu Inc, according to two sources familiar with the investment.

The e-commerce venture, which will be 70 percent owned by Wanda and 15 percent held by Tencent and Baidu respectively, is set to be announced later this week, the people said.

The venture will unite three of China's most powerful non-state companies. For Wanda, the tie-up with Tencent and Baidu opens the door to new opportunities in the world's biggest e-commerce market as the rise of smartphones creates new business opportunities.

Wanda is a commercial property, luxury hotel and film conglomerate controlled by Wang Jianlin, China's wealthiest billionaire with a net worth of $16 billion according to Forbes.

Wanda, which bought U.S.-cinema operator AMC Entertainment Holdings Inc in 2012, operates 83 department stores in major cities throughout China.

Shenzhen-based Tencent, a social media and video games mammoth, is China's biggest listed internet firm with a market capitalisation of $156 billion. Beijing-based Baidu is China's dominant search engine provider.

In July, Wang Jianlin said Wanda was planning a 50 billion yuan e-commerce business without disclosing who the other investors would be.

A Wanda spokesman declined to comment, as did spokeswomen for Baidu and Tencent.