Mexico's president says his country won't be paying for a wall along its border with the US.

Donald Trump has signed an executive order to begin its construction and says taxpayers will be reimbursed by their southern neighbour.

However Enrique Pena Nieto has once again insisted his country won't be paying for it, despite what the American President claims.

Arturo Sarukhan who used to be the country's ambassador to America, says it's pointless: