Former Mexico president Vicente Fox, speaking on BBC HARDtalk, tells US President Donald Trump to "go to hell".

He said: "He complains about Mexico. Why doesn't he stop drugs circulating in United States?"

Mexico is a key transit route for illegal drugs entering the United States. The New York-based think-tank Council on Foreign Relations estimates that 90% of cocaine sold in the US passes through the country.

Tens of thousands have died in drug-related violence in Mexico over the last decade.

On Sunday, President Trump said that Mexican President Enrique Pena Nieto “seemed very willing to get help” from the US regarding the drug cartels in the country.

A report by Associated Press last week said that President Trump had threatened to send US troops into Mexico during a phone call with President Pena Nieto, a claim that both the White House and the Mexican government have denied.

Mr Fox said: "He's saying he proposed to Pena that he's willing to send in the US Army. Go to hell Trump. Mexico does not admit in its territory by constitution armies coming from anywhere in the world."

He said "My worry is that President Pena does not have the courage enough to stand in front of him like we did when we nationalised the oil a 100 years ago."

Watch the full interview on Wednesday 8 February 2017 on BBC World News and the BBC News Channel or watch again on BBC iPlayer (UK only).