Hello and welcome to News Hour live from the BBC World Service in London. I'm Rebecca Kesby.

Now when Donald Trump was sworn in as US President earlier this week, one of his first announcements was to send 1,500 US troops to the southern border with Mexico.

That is to boost the 2,500 already there.

They're being tasked with installing barriers and infrastructure.

Today, though, an internal memo seen by our partners, CBS News,

suggested that 10,000 troops could actually be deployed there.

Immigration was a signature theme on the Trump campaign,

so it was no surprise when it appeared in his inaugural speech.

First, I will declare a national emergency at our southern border.

There we go.

Well, we're joined now live by Naomi Rucham, who's a correspondent for CBS News.

She's in New York at the moment.

Naomi, thanks for coming on.

First of all, can you tell us a little bit more about what was in this memo, who it was to,

and what kind of information it gives us about the Trump

migration plan? Well, Rebecca, good to speak with you. It certainly expands what we had already

heard just this week from President Donald Trump. In that executive action that Trump had

signed earlier this week on Monday when he took office. He did declare a national

emergency along the southern border. He ordered the Defense Department to provide troops and

resources. And then yesterday, the White House press secretary told reporters that he had signed

another executive order, that one deploying the 1,500 troops on top of the 2,500 who were already there.

But this recently released memo is what raises that number to potentially 10,000 soldiers.

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