The prime minister and Mr Corbyn were also asked about security - an issue that has risen to prominence since the London 
Bridge attack on 29 November.

Both candidates were asked by an audience member if they would prioritise the safety of citizens over human rights.

Mr Corbyn said the choice was "not an either/or".

He added the UK could not have security "on the cheap", and so Labour would "back the police up" with an increase in officer 
numbers.

When it came to his turn, Mr Johnson referred to the London Bridge attack, and said it was "extraordinary and wrong" that the 
attacker was given automatic early release from prison after an earlier terrorism conviction.