In a reply to a question asked by a Windows Phone user, WhatsApp support team indicated that the feature for voice calling for them is in developmental stage.

"WhatsApp Calling for your platform [Windows Phone] is still in the works," it said.

Must Read: Want to make voice call on WhatsApp? Ask someone to call you first

However, the email hasn't specified any  time-frame for its roll out for Windows Phone users.

"We cannot comment on any future release timelines but we appreciate your interest in WhatsApp Calling," the mail further said.

As of now, the WhatsApp's voice calling feature is available for Android users only.

Read More: How to use WhatsApp voice-calling feature

To avail the services, the Android users need to download version 2.11.528 from the Google Play Store.

The voice-calling can also be activated by receiving a call from someone whose voice-calling is already activated. After you get the call, you need to close and then reopen the app.