Sir David Attenborough's latest film is "the biggest message he's ever told", its directors have said - with one telling Sky News the broadcaster's final words on saving the world's oceans brought him to tears.

Ocean With David Attenborough, released in cinemas this week to mark the broadcaster's 99th birthday on Thursday, mirrors his lifetime as it takes viewers through 100 years of discoveries about Earth's seas.

The presenter hopes the film could help protect the planet from climate change.

He filmed with crew members over two years to show coral reefs, kelp forests and the open seas, to show why healthy oceans are so important for keeping the planet stable.

King Charles was among the guests at the premiere, held at the Southbank Centre's Royal Festival Hall in London, and spent time with Sir David on the red carpet.

Toby Nowlan, one of Ocean's directors, who has worked with the broadcaster for about 16 years, told Sky News entertainment correspondent Katie Spencer that the film was "very different" to any of his previous work.

"Nothing has come close to how important this film is," he said. "I remember sitting on a very cold beach off Sussex, filming with him, and we were doing the opening and closing words for the film.

"It was such a poignant moment. They were the most powerful words I've ever heard him say."

Sir David speaks of how, after almost 100 years on Earth, he believes the planet's oceans are the most important area to protect. "And if we save the ocean, we save our world," Nowlan said. "It really hit me and, yeah, I welled up."

He added that while Sir David's message is his "biggest" yet, ultimately it is one of hope.

"There's been a lot of doom and gloom over the last few years - we want the take home to be: if we save our ocean, we can make a huge difference for our climate, for our fisheries, for conservation, for food security."

'The man never stops'

Fellow director Keith Scholey met Sir David when he was a zoology student in the 1980s and started working with the broadcaster.

"I've had this privilege all my career of working with the great man," he said. "He is a huge team worker. He does what he does incredibly well, he expects very high standards, but it's always been a really fun process working with him."

He also has an "extraordinary" work ethic, Scholey said. "The man never stops and I think for him, time is very precious and you never waste time. He certainly never wastes time. And that's infectious to all the people who work with him."

And Sir David still has more to come, he added. "I'm sure this isn't his last documentary at all, and in fact I know there are other things happening, but I think this is a really important one."

Colin Butfield, another of the film's directors, said all the crew would get "swept up" in the broadcaster's enthusiasm and energy.

'If there's a strange creature at the end, he'll go anywhere'

Actor and travel presenter Sir Michael Palin, former US secretary of state and climate envoy John Kerry, and astronaut Tim Peake were also among the celebrities and well known figures at the film's premiere.

Mr Kerry told Sky News he was "genuinely optimistic" about the future of the planet and that Ocean would be "a new motivator and a strong message that people will find inescapable".

He added: "We all love the ocean. Everybody thinks it's just too big to be damaged, but that's not true. All around the world, it is currently being attacked by human beings in ways that are just not sensible, but easily correctable."

Sir Michael described Sir David's brilliance as a communicator - and joked about some of the situations he has filmed in over the years.

"He has a lovely way of telling stories and he obviously loves discomfort. If there's some sort of strange creature at the end of it, he'll go anywhere...

"He's had it far worse [than me]. I've been to various places that he's been to and I know what it's like filming in the cold, but, you know, he lies down to look at penguins. I must say, I walk through them, but there you go."

He said Sir David's output "leaves all the rest of us behind".

Sir Michael added: "I mean we've got to keep going because he's setting such an example. But he does it with a sense of wonder… he does it because he's amazingly curious about the world and still has this sense of wonder when he talks about what he's doing. It's really inspiring."

(c) Sky News 2025: David Attenborough's Ocean film is 'biggest message he's ever told'