Lexus announced the launch of its first hybrid sedan Thursday - the GS450h. Promoted by Toyota as the world's first hybrid with a powertrain specifically designed for a rear-wheel drive car, the big sedan will roll into overseas showrooms beginning next.

The GS450h is powered by a version of Toyota's Hybrid Synergy Drive, with a 3.5-liter V6 combined with an electric motor with a Nickel-metal hydride battery pack. According to Toyota, the combination gives the vehicle the performance of a 4.5-liter V6 (hence the 450h designation), with the best-in-class fuel efficiency of a 2-liter powerplant. The RWD powertrain includes a new transmission combining  an electronically controlled continuously variable transmission with a 2-stage reduction gearbox for the electric motor.

In the performance department, Toyota says the 450h hustles from 0-62 mph in 5.6 seconds. Not bad for a car with a fuel efficiency of 33 mpg (Japanese test cycle).

The hybrid features come at a premium price, though. The 450h is priced in Japan about $4,250 above a gasoline-only 4.3-liter GS, and a whopping $13,650 above the 3.5-liter version.

[Sources: Toyota, Reuters]