The UN has urged the Trump administration to immediately stop separating migrant children from their families at its border with Mexico. The practice is a serious violation of international law, it says.

The United States is the only country in the world that has not ratified the UN Convention on the Rights of the Child, and recently adopted a zero-tolerance policy with undocumented migrants.

Hundreds of children who crossed its southern border have been held in custody since October following an executive order issued by President Donald Trump.

The US defends its policy saying it's a way to stop "illegal" immigration.

So, can the UN convince the US to stop its policy of separating families?

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