Recently Microsoft had to relaunch its YouTube app for Windows Phone smartphones after Google’s request, but the search giant still blocked it. YouTube app had originally been removed from the Windows Phone store late this spring after Google complained to the software giant about its ability to download videos to the phones and preventing video ads from playing.

The app was relaunched last week, but just in a few days Google had to block it again, because Microsoft failed to make the browser upgrades essential to enable a fully-featured YouTube experience – instead, the company just re-released a YouTube app which violated Google’s Terms of Service. As a result, the app was disabled once again. This statement contradicts Microsoft’s public announcement made after the application was relaunched in August, when the company claimed that it was ready to provide great experience its consumers expect while addressing the concerns Google expressed earlier, including the addition of adverts.

At the time, Microsoft expressed hopes for continuing the collaboration with Google, but these prospects seem less hopeful now. The software giant later published a longer blog post by its vice president and deputy general counsel, David Howard, which explaining why their app was taken down again. They say that the reason was that Google asked Microsoft to switch the app to a new coding language, HTML5, which was quite weird since neither similar iOS app nor its Android fellow are built on HTML5. In result, experts from both companies acknowledged that creating a YouTube app based on HTML5 would be technically difficult and time consuming – perhaps, that’s why iOS and Android apps weren’t using it either.

So, after Microsoft re-published its non-HTML5 YouTube short-term app, Google decided to block it. It is unclear whether the current spat finds its way into a future antitrust complaint, but it is clearly not the first time YouTube appeared a pawn in wider clashes between Microsoft and other tech giants.

YouTube app used to be preloaded in iOS software, but was removed from the latest version of OS, because Google and Apple’s licensing deal wasn’t renewed. Though, Google launched a standalone version of the application through Apple’s App Store. Mobile is very important to YouTube, which accounts for over a quarter of its global watch time, and over 1 billion views per day.