Theresa May could bypass her Brexit “war Cabinet” by asking the full Cabinet to back her controversial plan for a customs partnership with Brussels, Eurosceptic ministers fear.

Mrs May has postponed plans to discuss Britain’s future customs arrangements with her 11-strong Brexit sub-committee on Thursday, having been outnumbered 6-5 last week by those who opposed the partnership idea.

As she considers her next move, Brexiteers have warned her she could face a revolt - and even a leadership contest - if she tries to steamroller opponents of the plan.

Boris Johnson has described the customs partnership proposal - which involves Britain collecting tariffs on behalf of the EU - as “crazy” but Mrs May refused to admonish him and Downing Street insisted she still has full confidence in the Foreign Secretary.

One Cabinet source said: “There is a growing feeling that the Prime Minister is going to avoid another confrontation with the Brexit sub-committee on a customs partnership, which she would lose, and just put the matter to a full Cabinet meeting where she has the numbers to win.