Nokia is building its own Windows RT tablet that is set to debut in early 2013. Sources familiar with Nokia's plans have revealed to The Verge that Nokia's tablet will include HDMI and USB ports and a 10.1-inch display that's similar to Microsoft's Surface RT screen. Nokia's tablet will also include cellular connectivity and we understand that AT&T will be one of the first to stock it in the US.

We're told that the large majority of Nokia's focus with its tablet is on a battery-equipped cover. Nokia will release a special cover for the tablet that envelops it like a book. Clicking into place, the cover provides a keyboard and a kickstand for the tablet. Nokia has also built a battery into the cover that can be used to power the tablet once it runs low on energy. Two USB ports on the case will also provide additional connectivity. We understand that the main tablet will have a 10-hour capacity with fast charging that boosts the battery capacity to 50 percent in a short period of time.

Our sources have revealed that the Finnish company is planning to build a small number of the tablets initially, with a view to potentially building a Windows 8 device later. Nokia's first tablet will run on an ARM chip with Microsoft's new Windows RT operating system. Recent reports have suggested that Nokia may unveil its tablet at Mobile World Congress in February.

We reached out to Nokia to comment on its tablet plans. A company spokesperson says it doesn't "comment on market rumour or speculation."