A TV documentary on life in the European Parliament caught the Brexit Secretary’s response when he was asked if he was finding the negotiations gruelling.
“Well, I’m really probably employed for my character more than my intellect,” he replied with a chuckle.
The comment follows Mr Davis raising eyebrows last year, when he told a radio interviewer that he "doesn't have to be very clever" to do his job.
Even before taking up his post, in July 2016, he was under fire for appearing not to understand how EU trade deals work.
Despite being a former Europe minister, he had called for Britain to negotiate lucrative individual trade deals with other EU countries after leaving.
In fact, it is a basic EU rule that member countries cannot seek out one-to-one trade deals with third countries but must negotiate as a bloc of 28, soon to be 27.
On LBC Radio last December, Mr Davis said: “What's the requirement of my job? I don't have to be very clever, I don't have to know that much, I do just have to be calm.”
That comment followed the Brexit Secretary’s claim that the pre-Christmas agreement with the EU was not “legally enforceable” without a future trade deal - which he later dropped.
Mr Davis was also caught up in the furore over his boast of 58 sector-by-sector Brexit impact assessments, which he then acknowledged did not exist.
The former head of the Vote Leave campaign, Dominic Cummings, once branded the Brexit Secretary as “thick as mince” and “as lazy as a toad”.
The latest gaffe comes in the final episode of Channel 4’s “Carry on Brussels” documentary, to be broadcast on Wednesday.
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