300 companies have already said they are interested in helping build a border wall between the United States and Mexico, Jane King at the Nasdaq reports.

According to CNN Money, the Department of Homeland Security’s Customs and Border Protection Agency asked the companies to submit a proposal to design and build structures near the United States border with Mexico. The proposals will start to come in next week.

The companies interested in helping range from construction companies to fence builders to concrete firms.

"There’s really nothing to say at this point. It’s all very speculative. Once we get the details, we’ll examine whether it’s something we’d move on," said Terry Willis of Caddell Construction who does major government construction projects around the world, including U.S. embassies and prisons. "Not every company is a serious bidder."

Congress will need to approve the funds that will be needed before construction of the wall can begin.