Donald Trump has defended construction of a wall along the US-Mexico border in a bizarre series of tweets in which he compared it to "the wheel" and boasted he understood technology "better than anyone".
"The Democrats are trying to belittle the
concept of a Wall, calling it old fashioned," Mr Trump wrote. "The fact is there is nothing else’s (sic) that will work, and that has been true for thousands of years. It’s like the wheel, there is nothing better.
"I know tech better than anyone, & technology on a Border is only effective in conjunction with a Wall. Properly designed and built Walls work, and the Democrats are lying when they say they don’t.
"In Israel the Wall is 99.9% successful. Will not be any different on our Southern Border! Hundreds of $Billions saved!"