Trump: 'Walls work — just ask Israel'

At a joint press conference Thursday with Colombian President Juan Manuel Santos, President Trump defended his proposal to build a U.S.-Mexico border wall to stop the flow of drugs. Following Santos' much lengthier, more nuanced explanation of how the best way to tackle the drug crisis is by "collaborating," Trump kept his answer short.

"That was a long and very diplomatic answer to your question. I will say it a little bit shorter: Walls work — just ask Israel," Trump said, seemingly referring to Israel's West Bank barrier. "They work. Believe me."

Trump insisted that "we have no choice." Minutes prior, the Nobel Peace Prize-winning Santos outlined Colombia's extensive efforts to combat coca production and promised to team up with the U.S. and other countries to "fight the other links of the chain, the intermediaries."

Catch Santos and Trump's responses below.