It’s a pretty safe bet that Samsung (005930) CEO J.K. Shin doesn’t see Microsoft (MSFT) as Samsung’s top partner. In an interview with The Wall Street Journal, Shin said bluntly that “smartphones and tablets based on Microsoft’s Windows operating system aren’t selling very well” and that his company has seen “lackluster demand for Windows-based products.”

This marks the second time this month that a Samsung executive has publicly knocked Microsoft’s mobile operating system, as Jun Dong-soo, the head of Samsung’s memory chip business, said last week that Windows 8 was “no better than Vista” and had failed to reignite demand for personal computers.

Given that Samsung relies primarily on Android and is planning to launch its own Tizen mobile platform in the near future, the company apparently doesn’t see any reason to play nice with Microsoft at all anymore.