Sylvester Stallone is such a cinematic icon that even when you're looking right at him one metre away, you're not really seeing him. You're filtering what you see through 30 years of Rocky and Rambo movies, among other things. His face looks strangely old, perhaps as it should since he's 61. But his hair is slightly too thick and too black. His hands are adorned with massive bits of jewellery, including a wristwatch on both wrists. And then he opens his mouth and there's that familiar gravelly voice. Although unlike either of his best-known characters, he's also warm, witty and deeply aware of what's going on in the world.

Over the past couple of years, he has revisited these two icons, claiming that his goal was to redeem them, to give them the send-off they deserved after less-than-satisfactory previous outings. Some suggest that this is driven by a newfound religious grounding, which is hinted at in the fourth Rambo movie's missionary characters before it turns into a violent bloodbath. (Turn the other cheek? Love your enemy? Hardly.) But of course the big question is whether Stallone feels like he's getting too old for all this.

"Well, I wanted to shoot this film somewhere easy, like Puerto Vallarta," he says, approaching the subject sideways. "I didn't feel like actually going to Burma and dying there in the jungle. But in the end we went to Thailand. It was a difficult film to make, but I'm glad we did it there, and that we got Burmese actors to play the soldiers, even though they were terrified to do it."

So how does he, at age 60, get into the kind of shape he needs to be for a role like Rambo? "I'm lucky because I'm under pressure to perform," he says. "If I didn't have to make these movies, I'd be eating 25 croissants and washing them down with beer! It's all goal-oriented. It's too hard to stay in shape without a goal. I remember a fellow actor, who I won't name, an upcoming star, who one day showed up with a much fuller head of hair than he'd had before. I asked him why he did it, and he said, 'It's a matter of fucking economics!' Well, I have this physicality, so I have to be willing to work with it, and sometimes that means looking like a fool."

He admits that directing himself in the movie was also a bit tough on him physically, laughing that it would have been so much easier to direct himself in a chamber drama. "But this was very difficult, and you start to feel the wear and tear, which means you compromise. Sometimes you have to settle, realise you're not going to get perfection. You don't have the strength to do 30 of these takes, so you just have to get the energy."

But he was never hurt while performing any of his stunts in the film. The injuries always came after the cameras stopped rolling, such as when he punctured his arm and had to be taken to hospital. "Everything in Thailand is dangerous," he exclaims. "The butterflies are deadly! There are huge snakes, and centipedes this big [he holds up a 1-litre water bottle]! You find something sleeping in your toilet that will eat you! On the other hand, everywhere you look there are 11 people on one moped, and no one is hurt!"

Getting older also means engaging with his children while he works on a film like this. he talks about how they would spy on him while he was watching the footage in his home cinema, then act out the scenes at school. "I had to detox them from Rambo," he says. "They were becoming little Rambettes and Rambolinas! And they would see a violent scene and say, 'Oh, another death," and yawn! So we had to go and watch a lot of Sponge Bob to get back to normal."

There's definitely a sense that Rambo feels like he's looking back on his life. "He's an errant knight," Stallone says. "He realises that all of his life has been for nothing, and he tries to pass on that cynicism to these optimistic missionaries. I actually put a lot of philosophy in this screenplay, but I made sure it was buried in there without it becoming a talking-head movie."

He also clearly spent a lot of time digging into the situation in Burma, most notably in the region where the pro-democracy Karen people group has been so violently persecuted by government troops. "We did a lot of research, and we have had many, many death threats. But the Burmese students are pleased to have something out there about their situation that's not news," he says. "As horrific and bloody as this film is: this is war, and it's civil war, which is by far the most vicious of all wars. The movie doesn't compare to what these people have actually gone through. Such as the immolation of thousands--not hundreds as the media have reported--of monks in recent months."

And he laughs when someone asks if he's heard anything, positive or negative, from the Burmese government. "No, nothing official," he say cryptically. "But then, they spend millions in America to promote their country as a tourist destination rather than a war zone."

This new Rambo follows Rambo III by a full two decades, and yet the film is shot in a 1980s style rather than the edgy hand-held thrillers of recent years. "I wanted to do an old-style action movie for an entire generation of moviegoers who hasn't seen one before," he says. "Who's the bigger savage wins!"

Are there any of his other roles he'd like to revisit? "I think the biggest mistake was the sloppy handling of Judge Dredd. It could have been much better, a lot more interesting," he says. "And Cobra could have been something more too--Bruce Springsteen with a badge! I'd also like to see how my character in Copland is getting on now."

When asked who his favourite actor is, he answers immediately: "Peter O'Toole for me is the guy. I watch him in The Lion in Winter all the time. Actually, my wife says that if she catches me watching it one more time she's going to stab me!"

And he also has an obvious love for the British film industry. "You have the best actors in the world. You've had to use your brains in your films, not just the bodies. Our movies are incredibly stupid because we have too much money."

He said it.

DORCHESTER, LONDON, 11.FEB.08