General Motors is looking to scale down production in the United States, in a move that would affect thousands of factory and white-collar jobs at the carmaker.

"Actions are being taken to reduce salaried and salaried contract staff by 15 per cent, which includes 25 per cent fewer executives to streamline decision-making," GM said in a statement on Monday.

GM said the decision was taken to ensure cash flow and adapt to "changing market conditions and customer preferences." This will include shutting plants at up to seven locations.

The closures will affect five sites in the US and Canada as well as two outside of North America.

The move flies in the face of promises by President Donald Trump to increase manufacturing jobs. There are growing concerns his tariffs on steel and other goods will lead to rising costs.

Trump's chief economic advisor, Larry Kudlow, is due to meet the chief executive of GM, Mary Barra, broadcaster CNBC reported.

Speaking to reporters, Trump said "we have a lot of pressure on them" and that he has already spoken to Barra himself.

"This country has done a lot for General Motors," Trump said. "They better put something else in."

The carmaker expects to move fewer vehicles next year. In particular, it expects a drop in sales of sedans, as it moves to focus on hybrid and electric cars as well as trucks.