The next generation Lexus RX has been spied testing for the first time, ahead of an expected reveal next week at NAIAS.

The next generation Lexus RX has been spied testing for the first time, ahead of an expected reveal next week at NAIAS.

The mid-size luxury crossover is about to reach its fourth generation which will bring an increase in size to distance itself from the more compact NX. Despite the full body camouflage, it's easy to notice the new RX will adopt an evolutionary design with a more generous front spindle grille and revised headlights equipped with LED technology. It's the same story at the back where the overall layout has been retained but we do notice a pair of big exhaust tips while the taillights will continue to spread onto the big tailgate.

Other details are not known at this point but Lexus could decide to offer the 2016 RX with a third-row seating option at an additional cost for drivers who need to carry up to six passengers. The prototype spotted by our spy photographers had a very increased ride height which could indiciate the engineers were testing the car's suspension system.

Lexus could decide to bring the new RX as early as next week at the North American International Auto Show (NAIAS) in Detroit, with the car scheduled to go on sale as a 2016 model year.

Next generation Lexus RX spied for the first time