Around 15 per cent of the automaker's North American jobs will go, with several model lines to be discontinued.

General Motors has announced plans to reduce salaried staff in the US by 15 per cent, and could close up to five factories there.

The company has "unallocated" production from three car factories (Oshawa, Detroit-Hamtramck and Lordstown), and two engine and transmission plants (Baltimore and Warren) after 2019.

GM has confirmed to the Canadian government it will close the Oshawa plant outside of Toronto, leading to a walk out by workers, and a lot of ill-feeling due to aid previously given to GM to keep the plant open and the company afloat.

It's unknown whether the other plants will close, but today's announcement certainly sets the stage for their possible demise. The General is due to begin contract negotiations with the United Auto Workers (UAW) union next year.

Products affected by today's announcement include Buick LaCrosse, Cadillac CT6, Cadillac XTS, Chevrolet Impala, Chevrolet Cruze and Chevrolet Volt.

While production of a few of these models may be moved elsewhere, some, like the Cruze, Volt, XTS and Impala, seem to be on particularly shaky ground.

With its reduced head count and production footprint, the automaker hopes to save US$6 billion ($8.3 billion) by the end of 2020.

This is just the latest round of downsizing at GM, which in recent years has sold the Opel and Vauxhall brands to the PSA Group, left Russia, withdrawn from South Africa and other African markets, and stopped selling vehicles in India.

In 2017 it also closed its Australian factories, ending local development and production of the Holden Commodore and its variants.

Outside of the US, GM has already confirmed it will close one of its three South Korean factories. It will close an additional two before the end of 2019.