A woman views the Chinese social media website Weibo at a cafe in Beijing on April 2, 2012. (MARK RALSTON/AFP/GETTY IMAGES)

SalesForce is expanding the reach of its service allowing brands to monitor conversations about their products on social media platforms, to include Russia and China.

The subscription-based service, dubbed Radian6, already keeps tabs on 650 million sources including Twitter, Facebook, YouTube, and LinkedIn, in 22 languages. The addition of Sina Weibo, a social platform similar to Twitter in China, and Russia’s VKontakte, similar to Facebook, could bring more than 1 billion more users into SalesForce’s purview.

Radian6 will be the first authorized application to provide comprehensive listening of public social media conversations in China and Russia in real time, according to SalesForce, which is based in San Francisco.

SalesForce could be following the example of consumer products companies and car manufacturers including Coca-Cola and Mercedes Benz, which have used Sina Weibo for individual marketing campaigns, said Jenny Sussin, an enterprise software research analyst at Gartner.

Global brands are likely tapping Chinese social networks because state restrictions prevent Chinese citizens from accessing major American social networks, she said. While she said VKontakte’s primarily Russian users might skew slightly younger than Facebook users in the United States, “it’s definitely a competitive advantage” for SalesForce, she added.

“VKontakte matters, but Chinese Websites are going to help them more in terms of existing business,” Sussin said.

SalesForce acquired Radian6 in 2011 for approximately $326 million.