A patent for a future Nokia handset design has potentially shed some light on what some mobile fans believe is the company's much-anticipated N99.

The patent , uncovered by Unwired , shows a dual-slide design - both the screen and the numerical keypad appear to be able to move independently.

There's no word on whether this design is anything to do with rumours of the Nokia N99, as plans to release the flagship handset itself have yet to be confirmed. However, the details revealed through diagrams on the patent do seem to have an awful lot in common to the alleged N99 design that was leaked to the press in January.

Conceptually, it reminds us of Samsung's F520 - a handset where the screen slides in two different directions to reveal two different sets of controls.

But, as is often the case with closely scrutinised patents, this Nokia double-slider may never make it into your pocket.