Jacob Rees-Mogg says Treasury 'fiddling figures' on Brexit
In the Commons on Thursday, Mr Rees-Mogg asked Brexit minister Steve Baker to confirm whether he had heard that officials were deliberately trying to influence policy in favour of staying in the EU customs union.
He attributed the remarks to Charles Grant, the head of the Centre for European Reform.
On Friday, Mr Baker apologised to MPs for saying Mr Rees-Mogg's account of the remarks was "essentially correct".
Mr Grant had denied making them and an audio recording emerged where he did not say what was attributed to him.
However, Mr Rees-Mogg said he stood by his original claim.
Mr Grant told the BBC he was surprised that Mr Rees-Mogg had not apologised to him.