Volkswagen's recall plan for emissions vehicles rejected by US regulators
California air quality regulators are rejecting Volkswagen's recall plan to fix vehicles programmed to trick government emissions tests.
The California Air Resources Board said the recall plan for vehicles including the Beetle and Jetta did not meet its standards and was " unacceptable".
The US Environmental Protection Agency said it agrees with the move but is working on a different timetable.
Volkswagen says it continues to work with regulators.
The company's recall plan for 2.0-litre diesel engines covers 500,000 vehicles.
A recall plan for 85,000 3.0-litre engines is due next month.
Volkswagen told regulators last year that it had installed software on its 2009 to 2015 diesel engine models to bypass government emissions tests.
The California Air Resources Board said the recall plan did not adequately identify the affected vehicles; did not include a sufficient method for obtaining the car owners' names and address and did not include adequate information on how the fix would affect future emissions results.
The state agency also issued a formal notice of violation against the German car maker
"VW's submissions are incomplete, substantially deficient and fall far short of meeting the legal requirements," Annette Herbert, head of the agency's emissions compliance, automotive regulations and science division wrote in a letter to VW executives.
VW said the rejection of its plan did not mean a recall would not go ahead.