Vultures are circling says Chris Moncrieff

n Is Boris Johnson determined to sweep Theresa May off her perch? That is certainly what many Tory MPs – and others – suspect about the mop-haired Foreign Secretary's 4,000-word Brexit 'manifesto'.

This immediately begs the question: How secure is May at the top of the Tory tree? It’s beginning to look as though someone - could it be Boris? - is shaking the branches and that the Prime Minister is wobbling a bit. But is Johnson risking his own political future by issuing what some of his critics regard as a naked personal challenge for the leadership?

Johnson fiercely denies this is his motive only a few days before the Prime Minister makes her major Brexit speech in Florence. He insists he is right behind her. But Home Secretary Amber Rudd denounces his action as ‘back-seat driving’, while Liberal Democrat leader Sir Vince Cable says May sits there ‘paralysed and impotent’.

Boris’s estimate of the cost of EU membership has now been officially challenged, and he appears to have imported a degree of acrimony into the Cabinet – the last thing the Prime Minister wants.

It is true that all those whose names have been bandied about as a threat to her leadership are saying, hand on heart, that they have no designs on her job. Well, they would, wouldn’t they?

But then politicians always say that, so you have to take their denials with a pinch of salt. Johnson’s epic on leaving the EU and pouring the money thus saved into the NHS has been met with angry demands from some Tories that he should be booted out of the Cabinet for what they regard as disloyalty.

However, Johnson is no political innocent and he must have been aware his dissertation would give rise to accusations of attempted power-grabbing on his part. Equally Jacob Rees-Mogg and others whose names have been bandied about as possible successors to the embattled Prime Minister are also adamant that nothing could be farther from their own thoughts. Tell that to the Marines!

But on top of all this, there is a body of Tory back-benchers who have been expressing disquiet about how the party is being run in the wake of the Prime Minister’s ill-judged decision to hold a general election. Theresa May would be well-advised to cling tightly to that tree-trunk in case more shaking of the branches topples her off.

n Does Brussels grandee, the pompous Jean-Claude Juncker really believe his speech about the EU's glorious future without the UK is causing Brexiteers to regret their decision?

If so, he is sadly deluded. In fact, it is having the opposite effect. What Juncker is saying in effect, without much subtlety, is the EU is heading for a United States of Europe, in which Brussels makes the major overall decisions, leaving it to member states to make the minor ones.

This would simply reduce the status of member states to that of a feeble county council, if even that. And there would be a grandiose new president equal in every respect to the powers of the President of the United States. A job that might appeal to Tony Blair? All this is precisely what the Brexiteers feared. Juncker, in his palpable innocence, has been making the case for them.

So what the EU bigwigs regard as Europe entering the sunlit uplands of a near paradise, the Eurosceptics see as a journey into impotence and at the mercy of a gang of largely unelected people with the gleam of unadulterated power in their eyes.

So, the Brexiteers have a lot to thank Juncker for.

n Sir Vince Cable, leader of the massively depleted Liberal Democrats, for Prime Minister? Sir Vince, who leads a dozen MPs at Westminster, thinks this is entirely plausible. He may be in a minority of one about that.

As the party meets in conference in Bournemouth, Sir Vince says he wants people to see the Lib Dems as a party of potential government, rather than just a powerless rump jeering at their opponents from the touch-line.

That is an entirely worthy ambition, but - and I do not want to rain on his parade - several light years away, although stranger things have happened.

It is all reminiscent of Lord (David) Steel’s absurd exhortation to the Liberal Party, of which he was then leader, to “go back to your constituencies and prepare for Government”. From that moment, the Liberals went into a tailspin, with a few hiccups along the way.

Sir Vince is duly warned.

n "If you go on doing what you have been doing, you'll go on getting what you've got."

This must rank as the most weird, bizarre and seemingly meaningless political quotation of the year so far. Perhaps the former Liberal Democrat leader Lord (Paddy) Ashdown knows what he is talking about – but he could be the only one.