Chinese Internet companies Sina and Qihoo 360 have initiated a partnership on a Three Kingdoms browser game that is expected to lead to further cooperation down the road, Marbridge Daily reports.

The game will be jointly promoted on the Sina Wanwan gaming portal and Qihoo 360’s Game Center. Chinese news portal Sohu claims that the partnership goes beyond traditional cross-platform agreements and extends to joint promotion, event planning and game content development. It also notes that this is just the first step in their cooperation, which will become increasingly more in-depth.

The deal is significant when taken in the context of China’s competitive landscape. Qihoo and Sina are both in close competition with Tencent and Baidu, so banding together makes a fair amount of sense.

Qihoo has had public disagreements with Tencent in the past, and its new search engine brings it head-to-head against Baidu. Meanwhile, Sina’s Weibo microblogging service is up against Tencent’s WeChat to become the preferred new communication standard among the younger generation.

With its 400 million users, Weibo has helped Sina take its place among the Chinese tech industry’s most influential companies, but it’s significantly smaller than the likes of Tencent, Baidu and Alibaba. Even as rumors continue to fly that Ailbaba or Baidu will invest in Weibo, a closer relationship between Qihoo and Sina will stir up even more speculation.

Reports that Baidu and Kingsoft are in negotiations to partner over security software, which has largely been Qihoo’s domain. Qihoo’s outspoken CEO Zhou Hongyi said earlier this month that he welcomes the competition, even as he dismissed the rumored link-up as a “joke”.

Sina and Baidu inked their own partnership last July. Alliances like these are becoming a common occurrence in the Chinese Internet space as the stakes get higher, and they’ll likely continue to shift as rivalries come and go.

Image via Flickr / evan.finn