According to reports, Nokia will be unveiling two - not three, as first reported - Windows Phone 8 handsets at its Nokia World event on 5 September.

One will be the Nokia Phi (pictured above, on the left), while the other is currently codenamed Nokia Arrow. The Nokia Phi will be the flagship device with the Nokia Arrow targeting the mid-tier market. 

Russian blogger Eldar Murtazin, who has a proven track record with Nokia scoops, has provided a few extra details regarding the Nokia Phi, adding to those revealed earlier in August. 

Murtazin says the curved AMOLED display will be marginally bigger than was first reported, measuring 4.7-inches – Nokia’s biggest screen to date. The Phi (also a codename) will be thinner than either the Nokia Lumia 800 or 900 and will feature a microSD card slot accessible through the polycarbonate unibody. 

However, Murtazin does report that the Nokia Phi, which will also fall under the Lumia banner along with the Nokia Atlas, will have a poorer battery life than its siblings, with just a single day’s use expected. 

According to The Verge both the Nokia Phi and Nokia Arrow will be available on the AT&T network. However whereas the Phi will be an AT&T exclusive, the Arrow will also be available on T-Mobile.

The Verge also reports that a third Windows Phone 8 Nokia handset, codenamed Nokia Atlas will be revealed shortly after Nokia World.

Details on both the Nokia Arrow and the Atlas are currently limited, but they be the two handsets seen next to the Nokia Phi in the picture above that arose from a previous leak.