Apple is reportedly testing out designs for its long-rumoured smart television hardware, Digital Spy reported citing The Wall Street Journal.

The Cupertino firm is said to be building prototype models of its so-called iTV devices in collaboration with Foxconn and Sharp.

Alleged inside sources told the publication that several trial models of the device have been tested, but it remains in the "early stages of testing" and is not yet a "formal product".

Speculation surrounding Apple's television ambitions reignited last week when CEO Tim Cook identified the sector as an "area of intense interest".

Sharp is said to be providing screens for the product, while Foxconn is the primary manufacturing partner, a role it has fulfilled for numerous past Apple hardware releases.

Apple is yet to officially confirm plans to move into the television hardware market, but many analysts believe this will change in 2013.