Microsoft has taken over Skype for $8.5bn (i. e. £5.4bn) but Cisco has recently announced about its decision to challenge the merger soon at one of EU's top court as it wants to ensure that Microsoft do not block any other video services in working at present.

According to statements of the European Union that came in October last year, it was said that the merger would not impede competition in the market, following which Cisco urged European Commission to introduce some open standards, like the ones that serve mobile phones to avoid any restriction on video services.

Cisco is another big name that is offering video conferencing service with name WebEx. The company has already appealed the European Commission’s decision on Microsoft’s acquisition and is all ready to challenge the same.

“Cisco does not oppose the merger, but believes the European Commission should have placed conditions that would ensure greater standards-based interoperability”, Cisco's video conferencing head Martin De Beer wrote in a blog post.

“Today, however, you can't make seamless video calls from one platform to another, much to the frustration of consumers and business users alike”, he added.

In reply, European Commission Spokesperson Antoine Colombani said that they will be defending the decision in court.

Skype is one of the most common video calling services that are serving people worldwide nowadays. The service has more than 650 million users worldwide. Microsoft announced about its biggest acquisition last year in May.

Open standards (as is demanded by Cisco) will not only allow potential video services between WebEx and Skype, but also among many other video services like Google Video, etc.