Grant Shapps was left red-faced after Kay Burley exposed his lack of Army knowledge.
The new defence secretary has been criticised for his lack of military experience and faced accusations that he only got the job because he is an ally of Rishi Sunak.
On Sky News this morning, Burley told him: “There has been a lot of criticism that you got your job because it was a job for the boys as opposed to knowing anything about the Ministry of Defence and our armed services.”
She then asked him if he knew how many ranks there are in the Army.
Shapps replied: “Not off the top of my head, but on your main question, what I would say is, look, what the Ministry of Defence needs is highly-experienced cabinet ministers who can run a complex infrastructure-orientated department.
“I’ve had a lot of experience of running large budgets and complex departments.
“I think it’s worth saying, by the way, as far as I can tell only two of the last fifteen defence secretaries have had any military background themselves. It’s not usual in a democracy, where we actually pride ourselves in having civilians run all elements of government, including our military, to have people from military backgrounds.
“What I do know is how to run a department.”
Burley then said: “Do you want me to tell you how many ranks there are? From field marshall all the way down to officer cadet, numbering 12 in total.”
A clearly-annoyed Shapps replied: “Very good. Thank you.”
Shapps was appointed defence secretary last week following the resignation of Ben Wallace. Incredibly, it is his fifth cabinet post in just a year.