Graham Norton has blasted big-name guests for "ruining" his talk show.

Graham Norton

Graham Norton

The 56-year-old presenter admitted there have been a number of Hollywood actors who have "killed" the vibe of his self-titled BBC programme but they don't realise why they have stopped their own episode from being "fun".

He said: "There's the guest sitting on the couch thinking, 'But I love this show. Tonight just, I don't know, it's just not that good tonight,' and you're like, 'Because you're on it. Because you're here. You're ruining it'.

"It happens quite often where people are like, 'Normally this show is so fun,' and I was like, 'Yeah, but you're here. You carry this with you. You kill every room you enter.' "

After a series of difficult guests, Graham admitted he now tries to pair their booking with that of a British comedian because they are able to help bring life back to the discussion.

Speaking in the US, he explained: "That is the joy, because if I'm getting nothing, if that is a bloodless stone then you turn to someone else, or I might be lucky to have a comic at the end.

"They can do 20 minutes, so off they go. And actually sometimes, it's as illuminating to see a really kind of stern actor who is not really good at telling their stories to see what makes them laugh, to see the comic is really tickling them.

"That's, in a way, more revealing than the answer to any question I could ask them."

Graham singled out Mark Wahlberg for particular criticism - and admitted he was relieved when he "fell asleep" mid-interview.

He said: "If they're disruptive then that is a bore and annoying. Like Mark Wahlberg, I think Mark got a bit confused about the jet lag and wine.

"He fell asleep -- that was the good bit. When he fell asleep, that was like we were able to tell stories. The show's going a bit better now, I wonder why? Oh, he's asleep.

"And at one stage, he climbed on my lap and was like pinching my nipples, and I remember afterwards thinking, 'wow, my 20-year-old self, my head would have exploded if someone would tell me he would do that', but my 50-year-old self was just like, 'Get off me.' "

And Graham - who praised past guests George Clooney, Bill Murray, Will Smith, Tom Cruise, Madonna and Russell Crowe - hit out at those who admit to feel "nervous" about being on the show.

He said: "I find actors being nervous so annoying. Like you know that thing: 'Oh, I was so nervous, I was vomiting in the wings. I needed a bucket in the wings before I could go on stage. I was so nervous.'

"You're in the wrong job! If a bus driver is afraid of his bus, get a new job. Just don't do that. So I have no patience for actors being nervous.

"I just think, 'Oh shut up. Okay, don't go on. See if I care. We'll all go home.' Nerves annoy me."