What it’s like interviewing the prime minister

I may have only been the BBC's political editor for just over a year, but it has been a year like no other.

A year of three prime ministers.

It has given me a whirlwind insight into our leaders at moments of their greatest triumph and vulnerability.

And it has left with me an overriding impression - of the overarching importance of character.

Coaching in how to come across in public can mould and tweak how a politician might appear, but their authentic character will always be clear.

Like for any of us, aspects of character lauded in some circumstances will be criticised in others.

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Prime ministers give interviews in three situations: moments of considerable pride, such as when they have just taken the job.

Moments of colossal jeopardy, when they have run out of better ideas. More on that in a bit.

And then at set piece moments, such as party conferences or when travelling abroad to international events.

The way these things work is a strict time allocation is agreed beforehand.

I try to make sure one of my colleagues is standing just out of shot but in my eyeline, so they can count down the number of minutes I have left on their fingers.

Having eight or nine minutes in total is often as good as it gets.

How does Rishi Sunak approach interviews?

Mr Sunak has sought to make a virtue of bringing a predictable stability to politics, after what came before - politics, he said, was no longer a "boxset drama".

And yes, it would barely be possible to caricature characters as different as Mr Sunak and Boris Johnson.

There is little chance of catching Mr Sunak out in an interview on policy detail: he is an assiduous and conscientious consumer of his briefs.

But the fluency I've seen away from the cameras often deserts him when they are turned on.

The PM's trip to California in March provided an opportunity for a sit-down interview

In her last interview as PM, Ms Truss insisted she would lead the Tories into the next general election

He reverts to pre-prepared stock answers and isn't particularly nimble.

When I asked him for his reaction to Prince Harry's claims of being caught up in a "near catastrophic car chase" in New York, he managed to refer to the recruitment of 20,000 new police officers back home.

He can come across, at times, as a little robotic.

Like Theresa May and Gordon Brown before him, he is not a performative politician.

Facing the cameras is a necessary part of the job, but not a part he appears to relish.

His approach - a safety first strategy - arguably works, up to a point.

A lack of ad-libbed flourishes creates fewer hostages to fortune and unexpected headlines.

But the conversation is often less engaging than it was with his predecessors and when he ducks questions, he really does duck them - and talks about something else entirely.

It leaves the interviewer - and more importantly you, as a reader, listener or viewer - none the wiser, and without the answer I have sought on your behalf.

So what about Liz Truss?

Ms Truss, in her temptation to be provocative in her words and in her backdrops, was again instantly revealing of character.

Shortly, after becoming prime minister, she took me and other interviewers to the top of the Empire State Building in New York of all places, to tell us she was willing to be unpopular.

Her confidence was palpable.

We all know how that turned out.

Just a handful of weeks later, my phone rang and with about an hour's notice I was invited into Downing Street to do what turned out to be her last interview as prime minister.

Why did she volunteer to talk to me then?

Bluntly, next to no one else was up for defending her, so she had to do it herself.

Outwardly, even then, the confidence hadn't entirely deserted her, in her words at least.

But her awareness of her own predicament had been becoming evident for days in her body language, most particularly frantic blinking.

And pauses after my questions some of which were big enough to drive a bus through.

Days later, she resigned.

And then there was Mr Johnson.

When I started in this job, Mr Johnson was prime minister.

The pressure over what became known as "partygate" was mounting.

Throughout, the essence of Mr Johnson's character came through.

The florid phrases, the sideward glances, his instinct for theatricality.

His comparisons would be stark - such as when he told me there were comparisons between Russia's actions in Ukraine and Nazi Germany.

He would duck and swerve questions like any other leader, but often memorably or colourfully.

His critics pointed to his rather liberal relationship with the truth, which caused him and those speaking for him no end of trouble - and was a major contributor to his downfall.

It is something I questioned him on directly.

When he was faced with grave threats to his premiership, I again got a last minute call to interview a prime minister in an almighty mess, and the apologies flowed.

Not long later, he resigned too.

Asking questions of prime ministers, on your behalf, then, is an ever changing art - where the personality of the person sitting opposite is the single biggest determinant of how to approach them - and what you are likely to hear.