Ms. McKay appeared before the committee on Wednesday morning during which she was invited to answer questions on the subject of Brexit and the Northern Ireland Protocol.
In response to a question put to her by another MP, Ms. McKay talked about how she was born in "Derry".
A short while later, Chair of the committee, Simon Hoare, MP, invited Gregory Campbell to put his questions to Ms. McKay.
"Good morning Ms. McKay - it's good to hear you are speaking from Londonderry," said Mr. Campbell.
"I think Londonderry was what you meant to say but didn't," he added.
Ms. McKay responded: "I am quite happy to refer to it as Londonderry if you want me to, Mr. Campbell."
After a brief interruption from the Chair, Mr. Campbell went on to question the authority with which Ms. McKay talks about Northern Ireland.
"You don't live here and haven't lived here for many years, I think that's the bottom line," said Mr. Campbell.,
Ms. McKay interrupted saying: "I never left Northern Ireland - I have lived for long periods in the North - what you have said is not the case."
Mr. Campbell then asked Ms. McKay if she had written any books about the "utter decimation of the Protestant community from the west bank of the city?."
Ms. McKay replied with a long list of examples of her work where she focused on how the Protestant community was "decimated by the IRA and other republican forces".
Ms. McKay also referenced a section in her book 'Northern Protestants: On Shifting Ground' where she wrote in great detail about Chairman of the Londonderry Band's Forum, Kenny McFarland who about growing up in the cityside of Londonderry and the upheaval when he was suddenly brought from his school by his father to New Buildings.
Mr. Campbell then went on to ask Ms. McKay about a particular quote in one of her books.
Chair Simon Hoare, MP, interrupted Mr. Campbell saying: "If this goes on we will draw proceedings to a close."
After this exchange the rest of the meeting proceeded normally.
A message from the Editor:
Thank you for reading this story on our website. While I have your attention, I also have an important request to make of you.
With the coronavirus lockdown having a major impact on many of our advertisers — and consequently the revenue we receive — we are more reliant than ever on you taking out a digital subscription.
Subscribe to newsletter.co.uk and enjoy unlimited access to the best Northern Ireland and UK news and information online and on our app. With a digital subscription, you can read more than 5 articles, see fewer ads, enjoy faster load times, and get access to exclusive newsletters and content. Visit https://www.newsletter.co.uk/subscriptions now to sign up.
Our journalism costs money and we rely on advertising, print and digital revenues to help to support them. By supporting us, we are able to support you in providing trusted, fact-checked content for this website.