David Davis has said he doesn't have to "know that much" or be "very clever" to do his job as Brexit Secretary – but that his main role is to simply remain "calm".

Davis, who is managing Britain's exit from the EU, made the comments as he was asked about the at-times frantic negotiations with European counterparts, which eventually resulted in a deal on Friday.

"What's a requirement of my job?" Davis asked LBC's Nick Ferrari on Monday (11 December).

"I don't have to be very clever, I don't have to know that much, I do just have to be calm."

Davis admitted last Monday's botched attempt to reach an agreement with the EU so that Brexit negotiations could move forward to trade had tested that ability.

"That did test the calmness a little bit," he said.

Davis also denied he would have to postpone his hinted retirement plans in 2019 should a Brexit deal not be fully sorted, saying: "Anybody can do details."

Davis's comments come after UK and EU negotiators reached a deal on Friday over a guarantee on EU/UK citizen rights, on a £39bn divorce bill and on a soft border for Northern Ireland.

The Brexit Secretary used Monday's interview to reaffirm Britain's commitment to the soft border question, claiming comments he made in another interview over the weekend were "completely twisted" by journalists.

He had told the BBC's Andrew Marr Show on Sunday the soft border agreement was "much more a statement of intent that it was a legally enforceable thing."

Denying he was suggesting the UK could back out of the deal, he told LBC: "What I actually said yesterday, in terms, was we want to protect the peace process, we want to protect Ireland from the impact of Brexit for them.

"And I said this was a statement of intent, which was much more than just legally enforceable.

"In other words, of course it is legally enforceable under the withdrawal agreement. But even if that did not happen for some reason, if something went wrong, we would still be seeking to provide a frictionless, invisible border with Ireland."

Commenting on other parts of Friday's deal, Davis added that Chancellor Phillip Hammond had "slightly mis-spoke" when he said the government would be forced to pay the "£53bn to £39bn" divorce bill.

He suggested the UK could back out of making the payment should there not be a forthcoming trade deal following the next round of negotiations with the EU.

Davis also responded to criticism he faced last week after telling MPs his department had not commissioned a single Brexit impact assessment to ascertain how leaving the EU might affect the UK economy.

He told LBC: "I don't actually believe economic forecasts, they've all been proven wrong – look at all the ones about Brexit."