Volkswagen has pleaded guilty to fraud, obstruction of justice and falsifying statements in its $5.7 billion settlement with the United States Justice Department.

Charges were laid after evidence appeared that the automaker was using hidden software to cheat on diesel emissions tests.

VW will pay $US2.8 billion ($3.7 billion) in criminal penalties and another $US1.5 billion ($1.9 billion) in civil fines after the guilty plea.

In total, VW is spending up to $US25 billion ($33.1 billion) to address claims from owners, environmental regulators, states and dealers in the US.

It has also offered to buy back about 500,000 vehicles in the US.

The company has admitted about 11 million vehicles worldwide contained the deceptive software, including about 80,000 cars in Australia made by VW subsidiaries Skoda and Audi.

The Australian Competition and Consumer Commission (ACCC) has initiated proceedings in the Federal Court against Volkswagen, Audi and Audi Australia over the scandal.

The US courts have found that company employees were rushed to deleted computer files and other evidence after VW’s admission.

Assistant US Attorney John Neal has described the scandal as a “calculated offence”, not a “momentary lapse of judgment”.

The judge set a sentencing date of April 21.

But VW investors expected the guilty plea, so its stock did not move significantly.

“Volkswagen deeply regrets the behaviour that gave rise to the diesel crisis,” the company said in a statement.

“Volkswagen today is not the same company it was 18 months ago.”