So, how will exiting the EU really affect how many foreigners come to live and work in the UK?

Let's start with the numbers.

There are about 3.5 million EU citizens living in the UK, and they make up about 7 per cent of the workforce.

Since the Brexit referendum, net migration from the EU to the UK has fallen to its lowest level since 2012, but EU migrants are still adding to the population.

In the year to March 2018 an extra 90,000 people came to the UK from the EU.

That's out of a total net migration to the UK of 270,000.

The Prime Minister Theresa May has

vowed to cut that number to below 100,000.

So what will happen to all these people on Brexit day?

Well, on March 29, 2019, nothing will actually change.

The UK and EU will enter a transition period, which lasts until the end of 2020.

EU citizens entering the UK and UK citizens entering the EU can still come and go as they do now, but from January 2021, under Mrs. May's proposed immigration regime, EU citizens will no longer have preferential access.

She wants to attract highly skilled workers from across the globe who can bring the biggest benefits to the UK economy, and to cut the number of low-skilled migrants.

So how would people prove they're highly skilled?

Well, people arriving after the transition period will have to meet a minimum salary threshold.

As of now, highly skilled non-EU migrants have to earn more than £30,000 a year to work here.

That's a threshold that 76 per cent of EU workers living in the UK would currently fail to meet.

There could still be a cap on the number of people allowed to enter.

The government currently caps the number of skilled worker visas issued each year to workers from outside of the EU, but it's unclear whether this restriction will continue and at what level.

And what about low-skill sectors?

Won't there be a skills shortage?

Well, potentially.

Business groups have warned that sectors like construction, catering, and social care rely heavily on EU workers.

There are ways around this.

One pilot scheme allows British farmers to bring in fruit and vegetable pickers for up to six months a year, but Mrs. May has already ruled out a wider system of sector-by-sector exemptions.

Another option would be to add EU nationals to an existing youth visa scheme that allows 18 to 30-year-olds from certain countries to come and live and work in the UK for two years.

Let's not forget about the Brits living abroad.

Estimates of UK nationals living in the EU range from about 900,000 to 1.3m.

Any new UK rules for EU migrants could be tweaked in response to whatever policy the EU adopts for British citizens in the bloc.

So will all of these efforts to reduce migration from the EU have a positive or negative effect on the country?

Well, one independent report from the migration advisory committee concluded that EU migration has been good for Britain overall, raising economic performance and improving public finances.

But as we know from the referendum, it's not just about the numbers when it comes to such an emotional issue.