Penny Mordaunt was missing in action while working with Lord Frost to such an extent that he often did not know where in the country she was, friends of the former chief Brexit negotiator have claimed.
It comes as foreign secretary Liz Truss faces accusations of “black ops” in an increasingly bitter row over attacks on the trade minister in the Tory leadership contest.
Leading Truss supporters, including Lord Frost, have suggested Ms Mordaunt is unfit to be prime minister.