Mercedes-Benz’s plans to diversify the A-class line-up is driven by a decision to switch from today’s sandwich-style platform architecture - in use since the appearance of the first generation model in 1998 - to a more conventional and cost-effective structure similar to that used by its premium-class rivals.“We will have a change of concept,” said Mercedes CEO Rainer Schmueckle. “It is important to have a platform that accepts engines from other model ranges and boasts reasonably high flexibility.”To achieve this goal, Mercedes-Benz has been seeking co-operation partners in recent times, with the view to sharing development costs on the next-generation A and B-class structure. Yet despite coming close to a deal with Fiat late last year, it appears Mercedes will go it alone in developing the new platform - almost certainly using a transverse front-engined layout and front-wheel drive - along with a new range of four-cylinder, direct-injection petrol engines. Daimler is not short of money to fund the development of a new small car platform; profits topped £2.5 billion last year.But the company is not ruling out co-operation. “We’re technically capable of occupying this segment on our own without help from an outside partner,” said Klaus Meier, marketing boss for the A-class. “However, it is a particularly hard-fought sector, and co-operation would help us to increase the economies of scale and reduce overheads. With this in mind, we’re continuing to speak to interested partners.”The one big question mark hanging over the new A and B-classes is the cost of developing the proposed common-rail diesel engines. Given the figures involved, Mercedes-Benz is keen to strike up an alliance with other car makers. Talks with BMW are on-going, according to Autocar sources, suggesting the next generation of Mercedes-Benz’s small cars could use the same Peugeot-developed diesels as the Mini.