The US president was asked by reporters at the White House on Saturday about a Washington Post report suggesting smugglers had already succeeded in cutting through sections of the barrier using everyday household power tools.
“I haven’t heard that. We have a very powerful wall”, Mr Trump responded. “But no matter how powerful, you can cut through anything, in all fairness. But we have a lot of people watching.”
“You know cutting, cutting is one thing, but it’s easily fixed. One of the reasons we did it the way we did it, it’s very easily fixed. You put the chunk back in. But we have a very powerful wall. But you can cut through any wall.”
The president’s less-than-reassuring remarks mark a significant U-turn from his blustering performance when he last visited a construction site near San Diego, California, on 18 September, when he described the barrier as “virtually impenetrable” and a “world-class security system”.
A signature campaign promise first raised by the president on Twitter in August 2014, Mr Trump’s “big, beautiful” border wall has been dogged by setbacks since his inauguration.
Having initially promised his supporters Mexico would pick up the tab for its construction, the president was ultimately forced to ask Congress for $5.7bn (£4.4bn) in federal funding, which was rejected by House speaker Nancy Pelosi and Senate minority leader Chuck Schumer last December.
Mr Trump baulked at the Democratic leaders’ offer of $1.4bn (£1bn) as a compromise, bringing about a record-breaking 35-day government shutdown that lasted well into January.
The president finally declared that the “crisis” in illegal immigration at the US southwestern border constituted a a national emergency in February, invoking powers that enabled him to bypass congressional objections and reclaim funds from existing military projects in order to pay for the project.
That decision was met with an outcry and saw both the House of Representatives and Senate pass a motion of disapproval calling for the declaration to be revoked, which the president swiftly vetoed when it landed on his desk in the Oval Office.
So keen to get the project underway, the president had a plaque added to an existing section of fencing put up under Barack Obama in 2009 laying claim to it as the start of his own grand undertaking.
This is the plaque marking President Trump’s first Border Wall section in Calexico. It’s beautiful. 🇺🇸 pic.twitter.com/4ywpSOHlxH— Ryan Fournier (@RyanAFournier)April 5, 2019
He also regularly tweeted pictures of labourers repairing existing barriers, claiming their efforts were new segments going up.
Great briefing this afternoon on the start of our Southern Border WALL! pic.twitter.com/pmCNoxxlkH— Donald J. Trump (@realDonaldTrump)March 28, 2018
When construction work did press ahead in earnest, the former property tycoon was insistent on micromanaging it and complained that early sections going up were “ugly”, according to a Post report in May.
To remedy that, the president reportedly demanded that workers paint the structure black so that its surfaces might better absorb the heat from the blistering summer sun, making it tougher for would-be illegal entrants to climb.
He also suggested adding a row of spikes to the top to ensure maximum injury would be inflicted on anyone who made it that high. Both suggestions had to be dropped after engineers explained such measures would be too impractical to execute and too costly to maintain.
Most absurdly of all, it emerged last month that Mr Trump had allegedly proposed having snipers shoot approaching migrants in the legs to disable them and having a moat dug along the 1,954-mile length of the wall lined with ravenous snakes and alligators as a further deterrent.
That last idea provoked particular ridicule, not least when it emerged both Mr Obama and satirist Stephen Colbert had previously suggested it as joke and when Mr Trump angrily denied having ordered a “moot” on Twitter, the typo quickly going viral.