Nokia is expected to launch a new line of phablet products next month, Digital Spy said citing Reuters.
The Finnish firm is preparing to announce more than one new mobile device at a New York event in September.
A source close to the company leaked the information, but refused to give any details of the price and specifications.
Previous reports have suggested one of the phablets may be a 5.2-inch Lumia 825 handset - the biggest yet in the Lumia Windows Phone 8 range.
A leak by Chinese website Dopsy.com claimed last week that the device will have Qualcomm's 1.2GHz Snapdragon 400 with an Adreno 305 GPU.
The speculation joins existing rumours that the company will also unveil a Windows RT tablet at the same event.