Mercedes-Benz is developing an extended range of AMG Sport models to be positioned underneath its traditional line of AMG cars, in the international markets, our sister publication Autocar UK has revealed.

Intended to challenge the various performance orientated models from the Audi Sport and BMW M Performance line-ups, the new AMG Sport models are set to receive exclusive exterior and interior styling touches and upgraded engines. They'll also use uniquely calibrated chassis tuning and electronics, according to sources familiar with Mercedes-Benz’s plans.

As with the performance car strategies pursued by Audi and BMW, Mercedes-Benz plans to offer its upcoming AMG Sport models with a choice of either petrol or diesel engines, although not in every model.

Among the features differentiating them from the standard Mercedes-Benz models upon which they are base will be widened tracks similar to those used by full-blown AMG models. “We have identified growing demand for our more overtly sporting models, both in petrol and diesel guises. We intend to extend our range with a new line of models developed in partnership with AMG,” an insider revealed to Autocar UK. Included in the new AMG Sport line-up will be models from the A, C, E and S-class line-ups together with variants based on GL- and M-, GLK- and GLA-class.

Among the first of Mercedes-Benz’s new AMG Sport models will be the upcoming C450 AMG Sport. Planned to make its public debut later this year, it runs a tuned version of the C400’s turbocharged 3.0-litre V6 petrol engine that produces a claimed 367bhp. That's 34bhp more than the standard C400, but over 100bhp short of the upcoming C63 AMG, which runs a new twin-turbocharged 4.0-litre V8 powerplant.

Also under development and planned for launch in 2015 is an AMG sport variant of Mercedes-Benz’s new BMW X6 rivaling M-class coupé.