Volkswagen's top U.S. executive knew the carmaker might be breaking U.S. emissions rules as long as 18 months before it admitted cheating diesel tests to regulators, he will tell a panel of U.S. lawmakers on Thursday.
The admission by Michael Horn, in a written testimony to a congressional oversight panel a day ahead of Thursday's hearing, is likely to raise questions about why the German company did not act more quickly to tackle its wrongdoing.
Almost three weeks after it confessed publicly to rigging U.S. emissions tests, Europe's largest carmaker is under huge pressure to identify those responsible, fix affected vehicles and clarify exactly how and where the cheating happened.