According to reports in the technology press, the Optimus G will come with a 1.5GHz Snapdragon S4 Pro APQ8064 at its heart.
It is claimed to be the first Long Term Evolution (LTE) phone with a quad-core CPU, enabling fast mobile broadband services backed by a speedy processor.
Other features of the premium smartphone include a 4.7-inch 1280 x 768 True HD IPS display, 2GB RAM, a 13-megapixel camera, 1.3MP front camera and a large 2,100mAh battery.
The phone is fully integrated with LG's touch technology, and the 8.45mm thick body has been achieved because LG was able to reduce the air gap between the display and the surface, while also cutting the size of the bezel to just 3mm.
However, the phone will debut with Android 4.0 Ice Cream Sandwich, rather than the latest Jelly Bean release.
The Optimus G will launch in Korea next month and then expand to Japan on NTT Dotcomo in October or November.
A worldwide launch is expected later in the year, with more details to come at the IFA 2102 event in Berlin, which gets underway this week.