Ed Balls did not hold back as he interviewed Edwina Currie on Monday's Good Morning Britain.
Ed, 54, and his co-host Susanna Reid invited Edwina onto the ITV breakfast show to discuss the increase in National Insurance payments.
Unsurprisingly, Edwina, 75, jumped to Boris Johnson's defence as she insisted his National Insurance hike is the right thing to do.
The mother-of-two began the war of words by saying: "I'm sorry Ed Balls, you're the former Chancellor and you deserve every penny you get, but you're gonna be paying a lot more money!"
With a grin on his face, Ed replied: "Former Chancellor, not quite Edwina, just an aspirant chancellor. I was Shadow Chancellor, never made the job.
"But back in 1992 when you were a very close part of John Major 's government, John Major made a manifesto commitment in 1992 not to raise taxes.
"In his biography, Norman Lamont tried to persuade John Major not to do it. John Major made the pledge, then he had to raises taxes lots and lots of times and trust collapsed in the government and you lost the 1997 election.
"Is there a danger that Boris Johnson and Rishi Sunak are making the same mistake as John Major?" Ed asked.
Edwina didn't react to Ed's subtle dig at all, but she did answer the question without hesitation.
The former Tory politician had a four-year affair with ex-Prime Minister Sir John Major.
The pair had a relationship back in the 1980s when Edwina was a backbencher and before he became PM.
Edwina revealed the romance in her bombshell book Diaries back in 2002, along with the revelation he wore 'big, blue underpants'.
In a press statement at the time, Major said that he was "ashamed" by the affair and that his wife had forgiven him.
In response, Edwina said "he wasn't ashamed of it at the time and he wanted it to continue."
Good Morning Britain airs weekdays at 6am on ITV and ITV Hub.