Matthew Hancock came slightly unstuck when faced with questioning from Andrew Neil, after the BBC presenter pointed out a flaw in one of his economic arguments.
In a speech today, George Osborne will outline plans to try and force future governments to maintain a budget surplus when the economy is growing - much like Sweden and Canada.
Hancock, the Paymaster General and Osborne ally, had been dispatched to the Daily Politics to explain the policy. But he got into an argument with Neil about "fiddling" after it was claimed Sweden would not run a surplus this year.
"How big is the Swedish surplus?" @afneilJune 10, 2015
Neil asked Hancock: "How big is the Swedish surplus?"
The minister replied: "You tell me the figures."
An unimpressed Neil hit back: "I don't work for you. You're the one who has cited the Canadian and Swedish surplus as being examples of what the British government is now going to follow. So how big is the Swedish surplus?"
Hancock said again: "You tell me." Neil revealed: "They're not running a surplus this year."
Hancock said the government wanted to run a budget surplus so "should there be problems in the future we are better prepared so we fix the roof, as they say, when the sun is shining".
And he accused Neil of "fiddling around" with the precise budget figures in another country rather than focusing on the wider issue. "I'm not doing any fiddling," Neil insisted.