Clive Owen, Keira Knightly and Ioan Gruffudd attended the premiere

"Antoine Fuqua (the director) had to delete some of the action to get the PG 13 certificate," Bruckheimer told BBC News Online.

The film, which had its UK premiere in London on Thursday, stars Clive Owen, Keira Knightley and Ioan Gruffudd.

King Arthur is released in the UK on 30 July with a 12A certificate.

The premiere in London's Leicester Square was attended by the movie's main stars, including teenager Knightly, who plays Guinevere.

Speaking about her character, she said: "As a 19-year-old woman, you want to see really strong women in the cinema."

Royalty was represented by Princess Michael of Kent, who was accompanied by her son Freddie Windsor.

Precise

Also present on the red carpet was a horse decked out in Arthurian battle costume, along with its rider.

The film takes Arthur's story back to the 5th Century - an academic expert was employed to try and make it as historically accurate as possible.

John Matthews, who has written over 40 books on the subject, believes the stories are based on a real historical figure who was a Roman commander on Hadrian's wall in Cumbria.

"It must be quite rare, if not unique, for Hollywood to say they want to get it right - this is the most accurate portrayal of Arthur yet," said Mr Matthews.

Ioan Gruffudd (left) plays the loyal Lancelot

The film's writer, David Franzoni, explained he wanted to do something new with such a well-known story.

"We wanted to go back in time to something that had never been done, giving them back their place in history," he said.

And while director, Antoine Fuqua, was a big fan of Excalibur as he was growing up, he also wanted to move away from the legend.

"I wanted the movie to be about King Arthur, not a magical sword. I believe in these times we need a real hero, and he was a real hero."

In Fuqua's version, Arthur (Clive Owen) is Lucius Artorius, a half-Roman centurion struggling to keep order in one of the furthest outposts of the Holy Empire.

Realistic

Ioan Gruffudd, who plays Sir Lancelot, thinks there is room for both mythical and historical Arthurian films.

"I was very familiar with the legend, the story has evolved and been embellished over the centuries, that's why you can make Excalibur and also this version," he said.

"In King Arthur, Lancelot is a darker, broader, angrier, warring character. I enjoyed that he was darker than the gallant knight in shining armour. It's much more realistic."

Clive Owen plays the title role of the king

Bruckheimer said he deliberately avoided using American actors.

"I think it would take away from the authenticity of the story."

Clive Owen insisted there was no time for any nightlife while on location in Ireland's County Wicklow.

"It was wrap, home, bed, sleep work," he said.

But the actors did manage to have some fun.

Gruffudd admitted to being so vain, that he curled his eyelashes every morning - and when Ray Winstone, who plays the knight Bors, found out, everyone began calling Gruffudd Sir Lashalot.

And while the film is very male-dominated, Antoine Fuqua believes this did not faze Knightley.

Tough

"When she was around, it was not dominated by males," he said.

John Matthews thinks the film's portrayal of the usually ladylike Guinevere as a warrior queen was realistic.

"Celts and Picts both had women warriors, and they were often naked - we couldn't have Keira naked, so we went for the next best thing," he said.

Mr Matthews reckons there are few historically authentic films around.

"Gladiator is pretty much an accurate portrayal of the time but Braveheart turned history on its head.

"We were setting out to entertain (with King Arthur), it's not a documentary, and there had to be some concessions. But it was good to be involved in something determined to be accurate."