Ford has accelerated development work on its Fiesta-based challenger for the 2011 FIA World Rally Championship, following confirmation by the sport's governing body of technical regulations for the series' new formula.

An agreement on engine specifications that will apply from the start of next season was crucial in enabling Ford of Europe and rally partner M-Sport to step up development of the vehicle, which will be derived from the highly successful Fiesta road car.

The World Motor Sport Council has agreed on the introduction of a 1.6-litre turbocharged engine, which can originate from a manufacturer's base engine or be purpose-built in accordance with the new rules.

"It's vital for the sport that we respond to greater environmental awareness and also reflect the direction that our road cars will take," Ford of Europe motorsport chief Gerard Quinn said. "It makes good sense to introduce the 1600cc turbo engine as early as possible, while using all the existing S2000 technical regulations that have proved so effective."

The Fiesta RS WRC will be based on M-Sport's Fiesta S2000 rally car, which was launched in 2009 and won its debut event in Monte Carlo. However, there will be significant differences between the two cars, not only with the new 1.6-litre engine, but also in terms of appearance.

Engineers from Ford and M-Sport are co-operating closely on the development of the new turbocharged 1.6-litre engine, in conjunction with acknowledged French tuning expert Pipo Moteur. The future WRC car engine is based on Ford's Duratec production unit.

"We started research several months ago in the expectation that the 1.6-litre turbocharged formula would receive the go-ahead," M-Sport managing director and BP Ford Abu Dhabi World Rally Team director Malcolm Wilson said. "It took a long time for the decision to be finalised but, now it has, the team is working flat-out and I'm confident we have the time we need to develop, build and test the engine to the high standards required before the start of the 2011 season."

"We expect to receive the first unit at the end of July and that will allow us to begin testing the Fiesta RS WRC with the new 1.6-litre turbo engine at the end of August. Before that, the team will test the Fiesta S2000 with a current Focus RS WRC 2.0-litre turbo engine, to gain an understanding of the behaviour of the car under turbocharged power."