Volkswagen chief executive Martin Winterkorn has resigned following the revelation that the firm manipulated US diesel car emissions tests.

Mr Winterkorn said he was "shocked" by recent events and that the firm needed a "fresh start".

He added that he was "not aware of any wrongdoing on my part" but was acting in the interest of the company.

VW has already said that it is setting aside €6.5bn (£4.7bn) to cover the costs of the scandal.

The world's biggest carmaker admitted last week that it deceived US regulators in exhaust emissions tests by installing a device to give more positive results.

The company said later that it affected 11 million vehicles worldwide.