David Davis's allies fear that he risks being "marginalised" if Boris Johnson is handed a new "super-charged" Brexit role in a forthcoming Cabinet reshuffle.

The Prime Minister is said to be considering moving Mr Johnson, the Foreign Secretary, in a "renewal" reshuffle which could see her axe as many as five ministers.

Mr Johnson could be asked to replace Greg Clark, the Business Secretary, with the portfolio significantly bolstered to give him more direct "ownership" of Brexit.

However allies of the Foreign Secretary said that he is likely to reject the move because he is "very happy" in the Foreign Office after several turbulent months. "The difficulty they will have is that they know they can’t sack him,” a source said.