Philip Hammond has had enough. ‘Theresa humiliated him at Davos,’ says a Cabinet ally, ‘then No 10 briefed he was being excluded from the round of Brexit speeches. You just don’t treat your Chancellor like that. They can’t keep pushing him around’.

A senior anti-Brexit Tory backbencher concurs: ‘She’s made it look like she cares more about keeping [junior Brexit Minister] Steve Baker happy than the Chancellor of the Exchequer. Does she really want people to think Baker and Jacob Rees-Mogg are running economic policy?’

Yes, she does. For the past few months the Prime Minister has been using her Chancellor as a human shield. Whenever her Kamikaze Brexiteers have to be appeased, it is Hammond who is offered up for sacrifice.

Dan Hodges says that Prime Minister Theresa May has been using Philip Hammond as as human shield and the Chancellor of the Exchequer has had enough

In December it was over the divorce bill. Last month it was the scale of changes to Britain’s trading relationship with the EU. Last week it was because of his unduly pessimistic tone whenever he addresses the great ‘opportunities’ of the post-Brexit era.

Whenever Hammond deviates a millimetre from the Government line, he is pounced on by his critics. And the Prime Minister is only too happy to let them pounce.

Compare Hammond’s regular punishment beatings with the largesse granted to those on the other side of the debate.

On Wednesday, Boris Johnson delivered a heavily trailed speech setting out his own personal vision of Brexit. Actually, to call it a speech would be generous. It was a rambling, incoherent improvisation masquerading as a political argument.

Senior Tories say that Theresa May (right) humiliated Philip Hammond (left) at Davos and the Prime Minister seems to treat junior ministers better than him

‘Fly over the Channel at Dover and you see how narrow it is, the ferries plying back and forth like buses in Oxford Street, and as you measure the blue straits with your fingers you can see that this moat is really an overgrown prehistoric river that once flowed down from Norway and was fed by its tributaries, the Thames and the Seine and the Rhine,’ was one of the more insightful passages.

But where Boris is indulged, Hammond is pilloried. Under licence from Downing Street.

‘For tactical reasons the Brexiteers don’t want to go for the Prime Minister yet. So they go for Philip instead – and it suits her,’ a friend says. ‘It means she’s out of the firing line.’ For the moment. But it’s a strategy that is as short-sighted as it is timorous.

It’s true that even some of the staunch Cabinet Remainers express frustration at the Cassandra-like tone of the Chancellor’s interventions. ‘He could do more to make the positive case,’ one concedes.

But Hammond reportedly remains perplexed by such criticism. He sees it as part of his job to echo the concerns of business and to fight internally for a Brexit that will allay their worries.

He is also one of a group of Ministers becoming increasingly frustrated at an obsession with the optics of Brexit.

‘Look at the transition period,’ says one. ‘We can’t have a double shock. One impact when we enter transition, then another when we finally leave. It may make the Brexiteers happy, but it could have a disastrous effect economically.’

Within Downing Street, the view is that Mrs May is doing a commendable if inelegant job herding the Brexit cats around her Cabinet table. But that is a niche perspective.

‘The fudge position isn’t sustainable,’ says one Minister. Another laments the indecisive choreography of their discussions on the issue. ‘What will happen is one side will make their case, then the other side will make their case, and then everyone will look at the Prime Minister and wait for her to say something or give her view. But she never does.’

Boris Johnson, who gave a speech on Brexit on Wednesday, seems to be pandered to by the Prime Minister, according to Tory sources

Theresa May is hoping to resolve matters at the Government’s upcoming away-day. But again, her focus is primarily on keeping the pro-Brexit side of her Cabinet happy. Or rather, keeping her pro-Brexit Foreign Secretary inside the Cabinet.

In contrast, Boris Johnson’s colleagues are now bored by No 10’s obsession with pampering his ego. Just as they are bored by his weekly hints at resignation. ‘It’s a long walk back from Chequers,’ one says dismissively.

It’s also a long drive back for a Prime Minister without a Chancellor. Not for the first time, May has taken her eye off the ball.

Managing her man-child Foreign Secretary is obviously important. But the relationship between a Prime Minister and Chancellor is the most vital in politics. It represents the spine of the Government. Shatter it, as Thatcher, or Major, or – ultimately – Blair found to their cost, and you break the back of your administration.

The irony is, there is not actually a great deal of difference between the instinctive positions of May and Hammond on Brexit. Both want as soft and pragmatic a departure as possible. Both recognise the inevitability, political necessity and irreversibility of the referendum vote.

Indeed, the only real difference is that the Chancellor was historically more Eurosceptic than his Downing Street neighbour.

But for the moment, May is not acting on instinct. She is acting out of fear. Fear of what will happen if she fails to appease the Eurosceptics. Fear of what will happen if Johnson does have the courage to finally resign.

Fear of being forced into the position of actually making a decision on Brexit herself, without her human shield to protect her.

But she should also be fearful of the implications of allowing the abasement of Hammond to continue. When a Chancellor is torn down, it doesn’t normally take long before a Prime Minister and Government follow.

I understand Boris Johnson has been giving the Cabinet the hairdryer treatment. ‘He’s obsessed with hairdryers,’ a bemused colleague explains. ‘Whenever the discussion turns to Brexit, he starts banging on about them. How Europe will force to us to fix our voltage to comply with new hairdryer regulations. And how we have to fight this so we can set our own hairdryer regulations. It’s all a bit weird.’ Or perhaps he simply recognises the famously unkempt Boris locks are under threat from Brussels bureaucrats.

Will House of Cards collapse on May?

The thinly disguised ambition of new Defence Secretary Gavin Williamson is starting to grate with his colleagues. As are his viewing habits. ‘He’s becoming a bit of parody,’ a Minister informs me. ‘He keeps telling everyone his favourite series is House Of Cards and he’s watched it a dozen times. And apparently he recently told his office to prepare to move into No 10.’

Of more serious concern is the way Williamson has been using increasingly inflammatory rhetoric to boost his profile. The Minister says: ‘This isn’t a TV show, it’s real life. Look at his comments about hunting down Isis fighters. The things you say and do in Government actually have a life or death impact.’

I’m told Theresa May has had little success reining in some of his excesses. ‘She sees Gavin as her chosen successor, so she’s going to stay loyal to him. And she thinks in response he’ll stay loyal to her,’ the Minister adds. Perhaps it’s Mrs May who could learn a few lessons from Frank Underwood.