David Davis is threatening to ruin David Cameron's election as Tory leader this week by refusing to accept a demotion in his Shadow Cabinet.
Friends of Mr Davis say he will walk away from frontline politics rather than accept the position of shadow Defence Secretary.
The contestants in the marathon to lead the Conservatives will cross the finishing line at 3pm on Tuesday. Polls suggest Mr Cameron will inflict a heavy defeat on the former front-runner. But he was warned against seeking to humiliate his rival when building his top team.
"David Davis has won a lot of respect for the way he has conducted himself ... I don't think the party in Westminster or the country would want to see him demoted," said a friend.
Suggestions that Mr Cameron might seek to sweeten the pill with an additional post of deputy leader have been rejected by the Davis team. Mr Cameron has repeatedly suggested he wants a "unifying" top team but is determined to stamp his authority on his party quickly.
He will dread seeing his election overshadowed by internal rows, particularly since he wants to mount a 20-day publicity blitz to "re-brand" the Conservative Party if he is elected leader.
He plans a series of high-profile events designed to convince voters that his election signals a radical departure for the Tories.
DAVID CAMERON'S FANTASY TOP TABLE
1. George Osborne, SHADOW CHANCELLOR
WHO IS HE? Every leader needs a best mate and George is Dave's.
WHAT HE SAYS: "The allegations are completely untrue," rejecting claims of Natalie Rowe, aka Mistress Pain.
WHAT THEY SAY: "George and his friends wanted drugs... they used to snort it through rolled-up bits of white paper as bank notes were unhygienic," Ms Rowe told the "News of the World".
DINOSAUR RATING: Cenozoic (welcome to the modern era).
2. David Willetts, EDUCATION
WHO IS HE? Which of his "Two Brains" thought Davis was a good idea?
WHAT HE SAYS: "I believe David Davis is that man," one Willetts brain said in September.
WHAT THEY SAY: "I believe David Cameron is that man," is what the other meant to say.
DINOSAUR RATING: Cretaceous (Tyrannosaurus dies out, snakes begin to appear).
3. David Davis, DEFENCE
WHO IS HE? Either humiliated loser or brave and principled campaigner.
WHAT HE SAYS: "I'm Mr Heineken. I want to reach the parts of Britain never reached before."
WHAT THEY SAY: "You could hear the sound of people throwing up into buckets at the sheer hypocrisy of the man" - Nicholas Soames warns against drinking too much Davis.
DINOSAUR RATING: Triassic (giant reptiles stalk the earth, but first warm-blooded creatures appear).
4. Boris Johnson, ENVIRONMENT
WHO IS HE? Surely Cameron wouldn't. Would he? Some say Boris is angling for Environment and Rural Affairs.
WHAT HE SAYS: "My temperament is so generally peaceable that some mornings I wake up and think I have no enemies in the world."
WHAT THEY SAY: "Peaceable - and deluded" - an enemy.
DINOSAUR RATING: Cenozoic (from 65m years ago; yesterday in Tory terms).
5. Liam Fox, HOME AFFAIRS
WHO IS HE? Ran cleverest campaign, splitting Davis vote then backing Cameron.
WHAT HE SAYS: "Unmarried mothers get protected too much," says Stuart Wheeler, the spread-betting millionaire who backed Fox.
WHAT THEY SAY: "Should he become PM, I would leave the country," says one Tory who has... er... doubts.
DINOSAUR RATING: Pre-Cambrian (earliest period; life emerges from slime).
6. William Hague, FOREIGN AFFAIRS
WHO IS HE? Columnist, author, millionaire, after-dinner speaker and - oh yes - former Tory leader.
WHAT HE SAYS: Backing Cameron: "The new Tory leader needs a certain quality of leadership which is hard to put your finger on, but you know it when you see it."
WHAT THEY SAY: "Good jokes, lousy judgement" - Tony Blair.
DINOSAUR RATING: Jurassic (heyday of of the big-beast carnivores).Reuse content