AUDI has raised the stakes in its battle to steal business sales from rival premium manufacturers with the launch of a Euro IV-compliant V6 diesel.

The 163bhp 2.5 TDI model has been upgraded so that from next week, all orders of Audi A4 saloon, Avant and Cabriolet, A6 saloon and Avant, and a new Allroad model with this engine will avoid the 3% benefit-in-kind tax supplement on diesel.

Cars do not have to comply with the stringent emissions rules until 2005 but the industry has seen increasing activity among manufacturers to beat the deadline and gain a competitive advantage over rivals.

So far, the new Toyota Avensis 2.0 D-4D is the only diesel on sale that complies with Euro IV rules, with a Toyota Corolla using the same engine due to go on sale on June 2. Audi's new A3 is launched in June with Euro IV diesels, while other summer launches of cleaner oil burners include the Volkswagen Touran, Fiat Punto and a version of the Vauxhall Astra.

Neither BMW nor Mercedes-Benz, Audi's two main rivals, have given a firm indication of when Euro IV diesel will be widely available, although BMW's 3.0-litre diesel is expected to become Euro IV compliant early in 2004.

Audi's new A3 is offered with two Euro IV-compliant diesels – a 1.9 TDI and 2.0 TDI. The A6 Allroad will be the first four-wheel drive vehicle to qualify for the strict emissions regulations. Cars ordered are expected to be delivered in 12 to 16 weeks.

Meanwhile, prices and specifications have been confirmed for the new Audi A3 which goes on sale on June 12.

The entry-level 1.6 will be priced at £15,190, with a £2,000 increase for SE or Sport models. Diesel starts at £16,390 on-the-road for the 1.9 TDI, while the 2.0 TDI is priced from £17,180.

The range-topping four-wheel drive 3.2 V6 Sport is priced at £23,665 on-the-road. Later in the year there will be a second FSI direct injection petrol engine in the range joining the 2.0 FSI, with a 1.6-litre capacity. Prices for the 1.6-litre FSI will be announced closer to its launch.

Standard equipment on all models includes alloy wheels, a radio/cassette player, electric windows and mirrors, speed sensitive steering, active front head restraints and an electronic stabilisation programme.

Sport models upgrade wheel size and design and add a CD/radio, trip computer, climate control, sports seats, sports suspension and a rear sun blind.

SE models have cruise control, automatic headlights, wood trim and an auto dipping rear view mirror, as well as a CD/radio and climate control.