The Tory leader and his Labour counterpart clashed on ITV, covering issues including Brexit, the NHS and Prince Andrew’s recent television interview.
Mr Corbyn dismissed the Prime Minister’s pledge to “get Brexit done” by the end of January as “nonsense” while Mr Johnson suggested his rival was “not fit to lead our country”.
Here are our five key talking points from tonight’s debate:
Boris Johnson said that voter’s options were “getting Brexit done” with him or “dither and delay with another referendum on the EU when Jeremy Corbyn can not tell us what side he would vote on”.
He added: “We are asking for a mandate to govern while Mr Corbyn is asking for a mandate to have a new negotiation.
Mr Johnson maintained the UK will leave the EU on January 31 but Mr Corbyn replied: “The idea that the Prime Minister’s deal can be dealt with and finished by the end of January is such nonsense.”
He said the PM was proposing a trade deal with the US which would take “at least seven years to negotiate” while also holding talks with the EU on trade, claiming: “The two things are actually incompatible.”
Mr Johnson later challenged the Labour leader about a future referendum, asking: “Are you going to campaign for Leave or Remain?”
Mr Corbyn replied: “I want to bring people together, therefore there will be a referendum in which that decision will be made by the British people and our government will abide by that decision.”
2. The Union
The second question asked by the audience was “is the union worth sacrificing for Brexit?”
Mr Johnson said that the price of a “Corbyn-Sturgeon” electoral deal will be a second referendum on Scotland.
Mr Corbyn said they had not done a deal with the SNP and “no deal will be done”.
Mr Johnson said the union is “of course” the most important thing.
Answering first, Mr Corbyn said: “The agreement that the Prime Minister… has put to Parliament was about creating a border between the Republic of Ireland and Northern Ireland, and creating a different customs arrangement for Northern Ireland with the rest of Ireland, having promised to the Democratic Unionist Party he would never do that.
“Clearly, there is an issue there. Clearly, there are issues all around about this deal he has proposed.”
Mr Johnson replied: “We have a deal that keeps the whole of the UK together as we come of the EU and, of course, Jeremy Corbyn and the Labour Party, be in no doubt about it, in order to secure power and the keys to number 10 are going to do a deal, or probably already have done a deal with Nicola Sturgeon and the SNP to form Corbyn-Sturgeon coalition and the price of that deal… would be a second referendum on the union with Scotland.”
3. The NHS
Mr Corbyn accused the Prime Minister of conducting “secret meetings” with the US about the NHS and a future trade deal.
The Labour leader said: “What we know of what Mr Johnson has done is a series of secret meetings with the United States in which they were proposing to open up our NHS markets as they call them to American companies.”
Responding, Mr Johnson said: “This is an absolute invention. It is completely untrue. There are no circumstances whatever in which this Government or any Conservative government will put the NHS on the table in any trade negotiation.”
4. Prince Andrew
Asked if the monarchy was fit for purpose, Mr Corbyn replied: “Needs a bit of improvement.”
Mr Johnson said: “The institution of the monarchy is beyond reproach.”
Asked if the Duke of York is fit for purpose, Mr Corbyn said: “Before we discuss Prince Andrew I think we should discuss the victims that are there because of what (Jeffrey) Epstein was doing.
“I think there are very, very serious questions that must be answered and nobody should be above the law, but the primary position ought to be the proper treatment of those people who were victims of the most appalling behaviour by apparently Epstein and many others.”
Mr Johnson said “all our sympathies” should be with the victims of Epstein, adding: “The law must certainly take its course.”
5. The Christmas Spirit
The most surprising moment of the night came when moderator Julie Etchingam asked Boris Johnson and Jeremy Corbyn to make a gesture of goodwill towards one another.
The pair crossed the stage and shook hands with one another.
In the spirit of Christmas, the prime ministerial hopefuls were later asked what presents they would buy for each other.
Mr Corbyn said: “I know Mr Johnson likes a good read, so what I would probably leave under the tree for him would be A Christmas Carol by Charles Dickens and he could then understand how nasty Scrooge was.”
Responding, Mr Johnson said: “I would probably leave a copy – since you want a literary reference – a copy of my brilliant Brexit deal.”
Pressed by host Julie Etchingham to give a non-political answer, Mr Johnson said: “Mr Corbyn shares my love of plants and trees. I think maybe some damson jam,” to which Mr Corbyn said: “I love damson jam.”