Mercedes-Benz unveiled the CLE-Class in July this year and we had the chance to sample the replacement for both the C-Class and E-Class with two doors a few months later. Meanwhile, the German automaker is preparing the next chapter in the model’s development with the upcoming launch of the AMG-branded versions. Today we can share spy photos of both the 53 AMG and 63 AMG models, set to make their full and official debuts at some point next year.

The photo gallery below contains photos of two different prototypes, both snapped earlier today on public roads in Germany. The hardtop test car with the blue roof is likely the CLE 53 AMG Coupe judging by those four round exhaust pipes at the back. On the other hand, the convertible trial vehicle should be the range-topping 63 AMG model, which has a slightly different exhaust layout in the rear fascia and a Panamericana radiator grille.

Gallery: Mercedes-AMG CLE 53 / 63 new spy photos

As for what’s happening under the bonnet, we’ve mostly heard rumours so far. The warm 53 model is expected to get a more powerful version of the brand’s 3.0-litre inline-six mill, which generates 375 bhp and 369 pound-feet of torque in the CLE 450 4Matic. In the GLE 53 SUV, the 3.0-litre twin-turbo produces 429 bhp and 413 lb-ft and we could probably expect the same output for the more potent CLE in cabrio and coupe forms.

The flagship CLE will be the 63 AMG model. This one is a big mystery regarding its powertrain because some sources claim it will borrow the new C63’s 2.0-litre turbo-four hybrid mill but that doesn’t really make sense considering customers can get a larger inline-six unit with the CLE 450 4Matic. Giving that 3.0-litre engine more power with the addition of an electric motor would make sense considering the E63 will also switch from V8 power to an electrified I6

In fact, it seems that the CLE 63 will indeed be a plug-in hybrid as there’s a charging port located on the rear bumper of this new prototype. That’s a rather unusual place for a charging port but it’s not new to Mercedes as the GT 4-Door Coupe also has it in that place.