The DUP leader made the claim on BBC radio this morning.
Speaking on the The Nolan Show on BBC Radio Ulster he claimed his party blocked the Protocol in October 2019.
"We actually did block it. We blocked it and [Boris Johnson] called a general election. The reason why he called a general election is because he coudln't get the EU withdrawal agreement through parliament because the DUP votes made the difference so we blocked it," he said.
The presenter, Stephen Nolan, put it to Mr. Donaldson that the Protocol was a direct consequence of the DUP's support for Brexit.
"But the end game for real people in this country is the DUP supported Brexit and here we are today with the conseqences of Brexit. There would be no Protocol, there would be none of this hassle on business if there was no Brexit. Hold your hands up and own it," the radio presenter said.
Mr. Donaldson contested this and claimed the Protocol was not the DUP's fault.
"I have to say to you and I will repeat what I have said and what we have said consistently, this is most certainly not what we supported. It is not what we voted for. The public record is there.
"We believe Northern Ireland should be treated in the same way as the rest of the United Kingdom, that there are arrangements that we supported. We've worked with the Alternative Arrangements Commission for a long time...to put forward what I believe were reasonable proposals that were capable of dealing with the issues which you refered to in relation to the EU single market and would not have required a hard border either on the island of Ireland or a border in the Irish Sea.
"So we have been consistent....in what we have said on this and therefore I do not accept your contention that this is somehow our fault. It is not. When we have a Prime Minister who gave a commitment and then did not honour that commitment and went ahead with something new and was warned it would be harmful to NI and would undermine our economy, would undermine political stability, he went ahead.
"Now I hope that the Prime Minister will still do the right thing. That he will, in the days and weeks to come, ensure that his Government takes the steps that are necessary to restore our place fully within the UK internal market and remove this unnecessary Irish sea border," he claimed.