In a major milestone, GM mulls selling Chinese-made cars in US

"If China's economy picks up and demand there recovers, GM may have to build the vehicle here in the US," he said, adding the Envision may even end up becoming a part of the US presidential campaign.

"There will be rhetoric on this in the campaign, particularly from Donald Trump."

McAlinden went further, suggesting Trump has "already bashed Ford for building plants in Mexico".

"That will probably be the extent of the political fallout. No one else in any party has taken such an interest in the issue."

Stephanie Brinley, a senior analyst with IHS, said: "Building close to where you sell is sound strategy and expected to remain the first choice－but in some cases, the volume justification means importing is the better solution. This appears to be true in the case of Buick."

She said that it was certainly conceivable another manufacturer may make a similar decision in the future, but that GM's move is not "necessarily indicative of an overall shift" of auto manufacturing from North America to China.

"Buick already imports some of its products, and reports are saying that Buick expects to sell about 30,000 to 40,000 units per year－while that volume will be notable for Buick's US sales, it is a fraction of GM's sales and manufacturing," said Brinley.

"GM will continue to source the majority of its North American products from plants in North America; if the car is imported, it is not expected to portend a large shift of US auto manufacturing to China. GM's overall import volume to the US, from any country outside NAFTA, was only about 92,000 vehicles in 2014."