Crown Prince Mohammed bin Salman of Saudi Arabia told President Trump on Wednesday that the kingdom intends to increase its investment and trade with the United States by at least $600 billion over the next four years, according to the official Saudi Press Agency.

The crown prince, the de facto leader of Saudi Arabia, told Mr. Trump that his new administration had the ability to create “unprecedented economic prosperity” in the United States, and that the kingdom wanted to participate, a statement from the Saudi Press Agency said.

There was no immediate confirmation of the call from the White House.

Mr. Trump has promised to accelerate investment in the United States, particularly to help revive manufacturing. While campaigning last year, he said he would use a mix of tax cuts and tariffs to force companies to invest in the United States.

On Tuesday, Mr. Trump announced Stargate, a joint venture between OpenAI, SoftBank and Oracle that is intended to create at least $100 billion in artificial intelligence infrastructure. The initiative could invest as much as $500 billion over four years.

Saudi Arabia was Mr. Trump’s first stop on his first overseas trip as president in 2017, a reflection of the importance he put on his relationship with the crown prince. During that term, the United States pursued major deals with the kingdom, including arms sales.

Since then, Mr. Trump and his family have signed several personal business deals in the Gulf region, especially in Saudi Arabia and the United Arab Emirates.