Cortana at the centre of Microsoft's smartwatch concept art

A series of concept images for Microsoft's rumoured entry into the smartwatch market have emerged and show the much–loved round watch face.

While there has been little concrete news on when the firm will be releasing the device, with Android Wear already available and Apple's iWatch expected later this year, Microsoft can't afford to fall behind its competitors in the wearable tech market.

Read more: A closer look at the potential impact of Apple's iWatch on the smartwatch market

The concept art shows the company's new voice-activated assistant, Cortana, at the centre of the device and the images, from designer Nadir Aslam, also display a leather strap and a round face like the one included on the Moto 360.

The device is also rumoured to boast a variety of sensors, including a heart rate monitor, accelerometer, gyroscope, GPS and a galvanic skin response sensor to measure sweat levels.

Consumers getting ready to part with their cash should note that the product's features are unconfirmed at this point. Contrasting information has also suggested that the device will eventually look more like the Samsung Gear Fit or Fitbit One and focus more on the sport and fitness audience.

Read more: Why Android Wear smartwatches just aren't smart enough

Information is thin on the ground so far, with suggested names ranging from the Microsoft Lumia Watch to Kinect Wear. However, if the firm can ultimately combine functionality and fashion when the product eventually launches, it'll surely be one to watch out for.