The head of the public health body leading the Trump administration’s response to the coronavirus has contradicted the president’s claim that a wall along the border with Mexico will help stop the outbreak.

“Going up fast. We need the Wall more than ever!” Donald Trump tweeted on Tuesday, in response to a tweet linking the construction of the barrier to the spread of the coronavirus.

But Robert Redfield, the director of the Centers for Disease Control and Prevention (CDC), dismissed that suggestion at a House of Representatives hearing the same day.

When asked by Democratic congresswoman Katherine Clark whether "structural barriers at our borders would be of any use in mitigating the outbreak," he replied: “Not that I know of.”

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Mr Trump has repeatedly sought to downplay the severity of the crisis, even as the number of confirmed cases in the US has risen above 1,000. Mexico, meanwhile, currently has only seven confirmed cases.

The building of a physical barrier along the border with Mexico was a key part of Mr Trump’s 2016 presidential campaign.

Last month the Defense Department sent Congress a request to shift nearly $4 billion from the military budget to pay for construction of the wall.

Tuesday’s tweet wasn’t the first time Mr Trump had linked border control with the spread of coronavirus.