Prosecutors in Stuttgart have hit the sports car maker with a €535 million ($853 million) fine for using non-compliant diesel engines.

The Stuttgart prosecutor's office has penalised Porsche €4 million ($6.4 million) for a "negligent breach of duty" relating to its use of diesel engines with emissions-test-cheating software.

The rest of the fine – €531 million ($847 million) – comes from a levy calculated from the "economic benefit" the company derived from its illegal activities.

According to prosecutors, "negligent breaches of supervisory duties" from the company's engineering department led to the sale of diesel vehicles which weren't compliant with emissions regulations.

The company is keen to point out these breaches occurred "several levels below the executive board", and it "never developed and produced diesel engines".

Porsche also says it will not appeal the fine, noting the "procedure against Porsche AG is therefore concluded".

Porsche announced it would stop offering diesel engines in its cars in order to concentrate on petrol-powered sports cars, plug-in hybrid drivetrains and electric vehicles in 2018.

Prior to this, Audi-developed diesel engines were available in its Panamera, Cayenne and Macan ranges.

German prosecutors have levied similar fines against other Volkswagen Group brands for their role in the Dieselgate affair, with Audi copping an €800 million ($1.3 billion) fine, while Volkswagen was penalised €1 billion ($1.6 billion).