Volkswagen said its former chief executive Martin Winterkorn has agreed to pay 11.2 million euros (13.6 million US dollars) in compensation for what the company called his failure to quickly get to the bottom of the scandal over diesel engines rigged to cheat on emissions tests.

The German carmaker also said it would be receiving 270 million euros from liability insurance against loss from the actions of directors and officers.

The company said in a statement that Mr Winterkorn “breached his duties of care” as chief executive, based on an extensive investigation by a law firm commissioned by the company.

The US Environmental Protection Agency caught Volkswagen using software that let the cars pass emissions tests and then turned off air pollution controls during normal driving.

Mr Winterkorn, who has denied wrongdoing, resigned a few days after the September 18 2015 notice of violation from the EPA.

Volkswagen has apologised and paid more than 31 billion euros in fines, recall costs and compensation to car owners.

US environmental regulators were alerted to the emissions problems in May 2014 by a study from the West Virginia University’s Centre for Alternative Fuels, Engines & Emissions.

Volkswagen, however, continued to assert that the increased emissions came from technical issues, not illegal software.

The investigation found that from July 27 2015, Mr Winterkorn failed “to comprehensively and promptly clarify the circumstance behind the use of unlawful software functions” in 2.0-litre diesel engines sold in the US from 2009 to 2015.

The company said Mr Winterkorn also failed to ensure that the company answered questions from US regulators “truthfully, completely and without delay”.

Settlements were also reached with other former VW executives.

Under the agreements, Rupert Stadler, former head of the Audi luxury car division, would pay 4.1 million euros, former Audi executive Stefan Knirsch one million euros and former Porsche executive Wolfgang Hatz 1.5 million euros.

Porsche is a part of the Volkswagen Group.