The two leaders interrupted the proceedings and shook hands on the promise after being prompted to do so by ITV host Julie Etchingham.
During the showdown, Ms Etchingham asked the two men: “Will you two look at one another and make a gesture to improve things today?
“Could you make a pledge and promise that whoever becomes Prime Minister will improve the nature of debate in this country.”
Mr Corbyn replied: “The debate in Parliament before it was dissolved was vicious and horrible and some terrible remarks were made particularly about women MPs.
“Mr Johnson and I agreed that this was unacceptable conduct and I absolutely agree with that.”
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Mr Corbyn and Mr Johnson then shook hands following the statement, with Mr Johnson adding: “I completely agree with what Mr Corbyn has just said.”
Later on in the debate both leaders were once again united on a pledge to end austerity after clashing about their proposed spending.
Both were asked if they will end austerity, to which Mr Corbyn said: "We will end austerity. We are absolutely clear about that."
Mr Johnson added: "Of course, I believe in spending investing massively in our public services but because we support the wealth-creating sector."