South Korea's Hyundai Motor Group said on Monday that it has signed a memorandum of understanding with Posco Holdings for cooperation on its planned US steel plant.

Posco will make an equity investment in Hyundai Motor Group's steel factory project in Louisiana, the group said in a press release.

The steelmaker was also considering selling some of the steel to be produced from the factory. Production is slated to begin in 2029.

The South Korean carmaker announced plans to invest US$21 billion in the United States with US President Donald Trump at the White House last month.

In a regulatory filing, Hyundai Steel said it would invest US$5.8 billion along with Hyundai Motor Group to build a steel plant in Louisiana with an annual capacity of 2.7 million tonnes.

Trump slapped 25 percent tariffs on South Korea this month, which were later suspended for three months. (Reuters)