Reality Check: How many EU nationals have been refused entry to the UK?
The claim: The home secretary has stopped lots of European Union nationals from visiting the UK.
Reality Check verdict: The UK refuses a tiny fraction of EU nationals who want to come here. It has to have very good grounds to do so. In the case of criminality, for example, a conviction even for a serious crime in not good enough - the individual must pose a current risk.
"If you ask the Home Secretary she'll tell you that she's excluded a very large number of EU nationals. If she has a need to do it she can," former attorney general Dominic Grieve told Radio 4's Today Programme.
As Mr Grieve was good enough to suggest it, BBC Reality Check did indeed ask the home secretary how many EU nationals she had excluded.
A Home Office spokesman got back to us and said: "Since 2010, we have denied entry to over 100,000 people, including over 6,500 EU nationals."
The reason it came up is that Justice Secretary Michael Gove, a Vote Leave campaigner, said: "Inside the EU we have to accept that anyone with an EU passport, even if they have a criminal record, can breeze into Britain."
People who are nationals of EU member states have the right to work or live across the EU, including in the UK.
The issue of border controls is separate; the UK has always maintained its own approach.
It is not part of the border-free Schengen Area and EU travellers coming through the UK's ports and airports have their passports checked.
Admission to the UK can be blocked "on grounds of public policy, public security or public health", according to EU rules. Under no circumstances can it be on economic grounds.
Refusal of entry on public policy or public security grounds must be done on a case-by-case basis rather than with a blanket ban.
A person must represent a "genuine, present and sufficiently serious threat affecting one of the fundamental interests of society".
The rules state that "criminal convictions shall not in themselves constitute grounds for taking such measures".
Last month, the immigration minister said the UK had prevented EEA/EU nationals entering the UK on public protection grounds in each of the last five years.
We do not have figures for the reasons behind refusals, but government statistics show that since 2010 the total number of EU passengers initially refused entry to the UK has been rising; in 2015 a total of 2,165 EU passengers were not allowed in.
To put that into context, in 2014 (the most recent figures available) around 35 million EEA and Swiss passengers, excluding Brits, arrived at UK border control points and 1,755 EU passengers were rejected. That's around 1 in 20,000 passengers (bear in mind one person could be a passenger many times in a year).