Boris Johnson has confirmed the UK will leave the EU on 31 October “come what may” if he is elected Conservative leader as he ruled out another extension to the Brexit talks.

The frontrunner in the race to be the next Prime Minister said on Tuesday morning it was a case of “do or die” when it came to delivering Brexit by the end of the latest extension period.

Johnson argued it was “fundamental to trust in politics” that Brexit is delivered, as he claimed May’s deal needed to be shelved and the so-called divorce bill of £39billion should be withheld until another agreement is reached.

Speaking to Talk Radio, Johnson said: “We are getting ready to come out on October the 31st. Come what may.”

When asked if that meant “do or die”, Johnson replied: “Do or die. Come what may.”

The former foreign secretary was then asked to rule out a further extension to the UK’s membership of the EU, to which he replied: “Yes, let me tell you why.

“Because it would be up to the Prime Minister of the day. I have myself to decide under the current terms of the extension that we have to apply for such an extension and it is up to the EU to decide whether to grant it.

“At the moment, the law says that the UK is leaving the EU – international treaty law -says the UK is leaving the EU on the 31st of October.”

Johnson claimed he could strike a deal with the EU which would see existing arrangements with the Irish border continue until trade deal has been signed.

“I think that the way to come out is with a standstill between the UK and the EU so that we keep going with the existing arrangements until such time as we’ve completed our free trade agreement and we use that period to solve the questions of the Northern Irish border. I think we can do that,” he said.

Such a position would see the UK needing to follow the EU’s regulations and customs rules to prevent the need for border checks on the frontier.