Audi is facing a shortage of luxury cars in the U.S.
The luxury arm of Volkswagen Group posted a 16 percent U.S. sales decline in December, compared with a year earlier, after experiencing supply issues.
Audi spokesman Mark Dahncke said the U.S. shortages affected the brand’s sedans, including its three best sellers: the A3, A4 and A5.
The brand blamed the constraints on delays in submitting cars for certification by U.S. environmental regulators.
Those delays stemmed from Audi’s failure to receive swift approval from European regulators who imposed new standards known as Worldwide Harmonised Light Vehicle Test Procedure.
Several automakers have struggled to get vehicles certified in Europe under the new, stricter standards there.
The shortages come as sedan sales are already ailing throughout the industry. In December, the A3, A4 and A5 posted sales declines of 61 percent, 56 percent and 41 percent, respectively.
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Dahncke said the shortages won’t be rectified until later this month or in February.
The European regulations that caused the delay — known as WLTP — were designed to slash emissions and more accurately gauge the road performance of vehicles.
They were implemented after the Volkswagen and Audi diesel car emissions scandal and other issues cast a spotlight on Europe’s need to bolster its standards for the sake of public health and the environment.
Follow USA TODAY reporter Nathan Bomey on Twitter @NathanBomey.