Barbara Ellen, Observer writer First, Robert De Niro walks out of a Radio Times interview with journalist Emma Brockes, because of her “negative inference” (nope, me neither). Then architect Zaha Hadid cuts short a tense Today interview on Radio 4, accusing Sarah Montague of not doing her research.

Most journalists have similar stories. I had Izzy Stradlin from Guns N’ Roses storm out because I had the temerity to ask about heroin references in songs the band had gone on record as saying were, um, about heroin. Once, a painfully sulky John Hurt seemed to hold me personally responsible for questions he hadn’t liked from a previous interviewer. Another time, Steven Berkoff snarled at my questions from the off, like a bear with its face stuck in a beehive, before finally stomping out.

It’s not as if anyone has been ambushed – these are pre-arranged, professional engagements Barbara Ellen

Unless interviewees have been tricked into the room on a promise of jelly and ice cream, there’s no excuse for such tantrums. While they’re not answerable as such, the fact is that, if they’ve agreed to do an interview, then they should be professional and do the bloody interview. They should also accept that questions will be asked – and the journalist isn’t some obsequious branch of their marketing team, whose only duty is to dribble on about how fascinating they are, darling.

Krishnan Guru-Murthy, Channel 4 news presenter I can’t help feeling sorry for the poor souls. For 99% of their working lives they are treated like gods by an army of assistants who dare not question a thing. Then along comes someone like me or you who wants to ask what they think, tease out an opinion or explore something done or said before. They hate it, and they panic. When I interviewed De Niro he was promoting another slightly disappointing comedy and was so obviously cringing from the moment he walked in to our interview room that it was like seeing a caged tiger at the circus. I almost felt guilty. I suspect this time he just lost control and couldn’t cope.

Robert De Niro: mind your inferences. Photograph: Ernesto Di Stefano Photography/WireImage

Actors are pushed out on to the publicity stage as good as naked. The PRs rarely seem to prepare them or warn that there’s a difference between Brad from IReallyLoveMovieStars.com at the junket and an interview with the British newspapers, Channel 4 News or Today.

I have some sympathy too for Zaha Hadid. She’d won a prize. In the normal world that provokes praise. In the media it invites questions. Of course, she’d have done much better to stay and point out the facts about her proposed Tokyo stadium, but it’s her right to walk, so long as she understands some people will have drawn what De Niro would call a “negative inference”.

The trouble when it comes to criticising bad manners is that I admit some of my questioning fails the dinner party test Krishnan Guru-Murthy

BE I appreciate what you’re saying about soul-sapping, confusing junket-type interviews. And yes, it must be a shock for cosseted stars to cope with more serious media (especially with cringeworthy product to push). But why do their lousy career choices and paper-thin skin have to be the journalist’s problem?

At least Hadid was on the radio. The number of times I’ve observed some monosyllabic, charmless celebrity buffoon I’ve interviewed mysteriously transform into a delightful, effusive television/radio interviewee… I personally believe that the famous behave far worse in print interviews, because there are no witnesses, and they can claim they’ve been “misrepresented” or “misquoted”, and the rest. So I’ve got a modicum of grudging respect for those who lose their cool during radio or TV interviews.

Saying that, what a wasted opportunity. Robert Downey Jr was a petulant man-brat during your interview. And why would Quentin Tarantino “shut your butt down”, instead of welcoming an intelligent debate on Django Unchained? These people have been famous for decades – do they seriously expect you to use the time inquiring as to whether they’ve been on the London Eye? I’m wondering if the aggrieved walk-out is almost turning into a scalp for celebrities? It certainly ramps up the publicity…

Watch Krishnan Guru-Murthy’s interview with Robert Downey Jr.

KGM That’s certainly true: the internet loves this stuff. Robert Downey Jr stoked his own viral walkout by tweeting and slagging me off on the radio. He probably thinks he came out of it well. Tarantino, to his credit, was different. He didn’t actually walk out on me but stayed until the end – long enough to realise, I’m told by a friend of his, he’d perhaps made a mistake. You are right, though: it is a massive wasted opportunity. These are intelligent people, usually, and some, such as Robert Redford, relish an intelligent chat. Sometimes a bit too much; when I talked about the Blurred Lines lyrics with Pharrell, he was so wound up about me questioning the sexual politics of “I know you want it” he kept arguing for 20 minutes afterwards while I was trying to get in the lift. If only they were all like Grace Jones – your interview with her last week was gripping. But you get much longer with them than we do in television. We get 10 minutes, if we’re lucky.

The problem is their people. The people who hover in the background waving when they want the questions to stop, who demand the interview isn’t broadcast when things go awry, and who threaten never to let you interview one of their stars again when you tell them where to jump off. The trouble is, some broadcasters give in. The entertainment shows know if they don’t do as instructed, their supply of guests will dry up. Even some news programmes have been known to bow to outrageous demands, such as sending questions in advance for approval. One PR told me the star I was waiting for had walked out on a previous interview because the room wasn’t cold enough. Funny thing is, the jilted broadcaster never revealed that, but just sucked up the bad behaviour. So no wonder the stars and their people become spoilt brats. It is our industry’s fault for letting them behave like angry toddlers in the first place. Am I going soft?

BE No, in your game, empathy is a strength. I agree with you about the wretched, warped system, though sometimes I’m suspicious that the famous hide behind it (and their people), because ultimately it suits them.

It’s interesting to hear that Tarantino and Williams were still willing to engage – it gives you a scintilla of hope. Of course, journalists mess up too – and the famous and the powerful are entitled to stick up for themselves, clarify their positions, correct mistakes and passionately disagree. What grates is when they try to make a virtue out of bolting, as if it’s some noble act of integrity – when all too often it’s about arrogance, vanity or weakness. It’s also absurdly rude – in what other business would it be acceptable for grownups to sulk, strop and run out of the room?

It’s not as if anyone has been ambushed – these are pre-arranged, professional engagements. However artificial and vexed the circumstances for both parties, surely there should be a covenant of courtesy to see it through? Then again, if you can’t beat ’em, join ’em – Krishnan, perhaps you could lead the way by walking out on your next snotty, difficult interviewee?

Watch Krishnan Guru-Murthy’s interview with Quentin Tarantino.

KGM There have been times when it crossed my mind, though in truth more out of boredom than fury. And I have threatened to leave a few times when PRs kept us waiting too long (for less than A-listers), on the bluff that they need us more than we need them. I’ve always thought extreme lateness is as rude as any walkout. The trouble when it comes to criticising bad manners is that I fully admit some of my questioning fails the polite dinner party test. But I’m not there for steamed fish and broccoli. And while questioning can sometimes be persistent, and on topics they wouldn’t choose themselves, I don’t attack the way I might with a wayward politician.

When it comes to Westminster dodgeball, as the political interview can sometimes become, a bit of rudeness from the journalist is often inevitable when questions are being avoided. For a while now, a vogue has been developing among politicians for out-bellowing the interviewer and interrupting the interrupter. Perhaps they think that if they look indignant and attack the question, the viewers will forget that it hasn’t quite been answered. And with legions of cheerleaders on social media, they can walk out of an encounter thinking it has gone brilliantly. But it is what the rest of the viewers think that they should worry about.Whether it is the walkout, the dodge or the temper tantrum, these tactics are all, as you say, a bit weak and foolish. Whenever anyone asks my advice (and amazingly, they do from time to time), I always say the same thing: answer the question and have a conversation you might even enjoy. Or don’t do the interview in the first place. I will defend anyone’s right to act like an arse, but if they do, they shouldn’t be surprised if anyone else decides to park their bike somewhere painful.