US President Donald TrumpPresident Donald Trump on Sunday urged foreign companies to expand investment in the United States and bring in expert personnel to train American workers in advanced manufacturing.In a post on Truth Social, Trump stressed the need for the country to relearn skills in industries such as semiconductors, shipbuilding, and high-tech machinery by learning directly from foreign firms making large-scale investments."When Foreign Companies who are building extremely complex products, machines, and various other 'things,' come into the United States with massive Investments, I want them to bring their people of expertise for a period of time to teach and train our people how to make these very unique and complex products, as they phase out of our Country, and back into their land," Trump said.He argued that such knowledge transfer is critical to restoring American industrial strength and ensuring lasting benefits from foreign investment. "If we didn't do this, all of that massive Investment will never come in the first place -- Chips, Semiconductors, Computers, Ships, Trains, and so many other products that we have to learn from others how to make, or, in many cases, relearn, because we used to be great at it, but not anymore," he added."We welcome them, we welcome their employees, and we are willing to proudly say we will learn from them, and do even better than them at their own “game,” sometime into the not too distant future!" said Trump.Trump's post comes a week after he warned foreign countries investing in America to abide by immigration laws after around 475 illegal workers were arrested after federal immigration authorities raided the Hyundai plant in Georgia. Many of the detained workers were South Korean citizens.Earlier this month, Trump said companies are increasingly choosing to build in the US to avoid tariffs and benefit from protective policies."Thousands of companies are coming into the US... Traditionally, car companies... They are coming from China, Mexico, Canada... They want to build here because, number one, they like to be here, and number two, the tariffs are protecting them. And number three, they want to avoid paying tariffs. When you build their cars here, you don't have any tariffs," he stated at a White House press conference.