Experts and construction companies have previously suggested the controversial wall could harness solar energy
Donald Trump has suggested covering his proposed border wall with solar panels.
The US president's suggestion came after the prospect had been put forward on several occasions in recent months.
Speaking to supporters in Iowa on Wednesday, President Trump claimed that those in attendance were the 'first group' he had told the idea to.
He explained: "We're thinking of something that's unique - we're talking about the southern border, lots of sun, lots of heat. We're thinking about building the wall as a solar wall, so it creates energy and pays for itself.
"This way, Mexico will have to pay much less money - and that's good, right?"
He added: "Solar wall, panels, beautiful. I mean... actually think of it: the higher it goes the more valuable it is. Pretty good imagination right? Good? My idea."
President Trump is reported to have first raised the prospect of a 'solar wall' with Republican congressional leaders earlier this month, with Axios reporting that the US president told lawmakers they could talk about the idea "as long as they said it was his idea".
However, one of the companies to submit a design proposal for the wall earlier this year had put forward such a concept.
As reported by Associated Press, the Las Vegas-based Gleason Partners indicated that panels could power "lighting, sensors and patrol stations along the wall".
Electricity generated could also be sold, the company argues, allowing the cost of constructing the wall to be covered "in 20 years or less".
In a Huffington Post article last December, activist Homero Aridjis and researcher James Ramey encouraged Mexico to build a solar border, claiming it would be a "truly beautiful wall - a symbol of unity, visible even from space".
The solar wall idea was also floated by energy experts Vasilis Fthenakis and Ken Zweibel in a Wall Street Journal article on March 7th, saying Trump should work together with his Mexican counterpart Enrique Peña Nieto on the idea to resolve the political impasse over the controversial wall.
While President Trump has continued promoting his campaign promise of a border wall, Congress has yet to devote funds to the costly project.
In a budget deal earlier this year, US$1.5bn (€1.34bn) was instead put aside to enhance existing border security.