Speaking to Sophy Ridge on Sky News on Sunday, the Prime Minister reiterated his insistence that there will be no checks on goods from Northern Ireland to Great Britain after Britain leaves the EU.
It comes after Labour leader Jeremy Corbyn said on Friday that his party had obtained a confidential government report, which he claimed proved that there would indeed be customs checks.
But, asked if there will be checks, Mr Johnson said: "No, absolutely not.
"The deal we've done with the EU is a brilliant deal and it allows us to do all the things that Brexit was about so it's about taking back control of our borders, money, laws - but unlike the previous arrangements it allows the whole of the UK to come out of the EU including Northern Ireland and the only checks that there would be, would be if something was coming from GB via Northern Ireland and was going on to the Republic, then there might be checks at the border into Northern Ireland in order to ..."
He said the leaked Treasury analysis document that Labour revealed on Friday was "wrong" to suggest there could be checks and even tariffs on goods travelling between the two parts of the UK.
"Yes (that's wrong)", said the Tory leader.
"Because there's no question of there being checks on goods going NI/GB or GB/NI because they are part of - if you look at what the deal is, we're part of the same customs territory and it's very clear that there should be unfettered access between Northern Ireland and the rest of GB.
"The only reason - this is another of these things that has been produced by the Labour party as a kind of distraction."
Also on the programme, Mr Johnson said that Jeremy Corbyn's policy of "complete free movement" is "absolutely not what people voted for".
He said: "You've seen quite a large number of people coming in from the whole of the EU, 580 million population, able to treat the UK as though it's basically part of their own country and the problem with that is there has been no control at all and I don't think that is democratically accountable.
"You have got to have a system by which politicians can say to people, well yes we are letting people in but we are doing it in a way that is controlled and checked."
On whether he can guarantee that the numbers will come down, he added: "Yes, I can make sure that numbers will come down because we'll be able to control the system in that way and what I don't think is right is to have an uncontrolled and unlimited approach to that."
Mr Johnson continued: "I don't think people in this country are hostile to immigration at all, let alone being hostile to immigrants, but they want it democratically controlled and that's what Brexit allows us to do."
He insisted the Tory manifesto offered a "massive programme of investment in public services".
He said: "If we get the chance with a majority government on Thursday to implement that manifesto, it will be transformative of our country, and it's not just Brexit.
"Brexit is indispensable, you can't move forwards without Brexit but this manifesto, if you look at what we are doing with roads, rail, telecommunications, 5G telephony, with gigabit broadband, this will bring the country together ."
The Prime Minister also refused to say whether he would resign if he fails to win a majority in Thursday's General Election, after Ms Ridge asked him three times.
He admitted he was nervous and “fighting for every vote” ahead of the poll, but when asked if he would resign if it did not go his way, he replied: “The choice on Thursday is unbelievably stark, it’s between going forward with a one nation Conservative government that can get Brexit done…
“Or spending the whole of next year in complete paralysis with two referendums, one on Scotland, one on the EU when Jeremy Corbyn cannot even tell us what his position is on Brexit and who is going to campaign for the deal that he proposes to do.”
Pressed again, Mr Johnson said: “If you don’t mind, Sophy, what I’m going to do is concentrate on the five days before us because that is what I think the people of this country would expect.
“We have got a very short time to get our message across, it’s a message of hope and optimism about this country.”