Rain and hail gave actress Emma Watson a soaking but failed to dampen fans' spirits at the world premiere of the new Harry Potter film last night in London.

19-year-old Watson took to the sodden red carpet in London's Leicester Square in a vintage dress by 1970s designer Ossie Clark.

Meanwhile, co-stars Daniel Radcliffe and Rupert Grint looked slightly bedraggled in suits, clearly having been caught by some of the rain.

But the fans of the teenage wizard, some of whom had waited since the early hours of the morning to catch a glimpse of the stars, still cheered and waved banners.

Many of the cast, including Watson, who plays Hermione Grainger, wore white ribbons on their wrists in memory of murdered actor Rob Knox.

Knox, 18, who played Marcus Belby in the latest Potter adventure – 'Harry Potter And The Half-Blood Prince' - was stabbed to death outside a bar in Sidcup, south east London, last May, just days after completing the film.

Treading the red carpet at the screening, Jessie Cave, who plays Ron Weasley's love interest Lavender Brown, said: "Rob would have loved to be here tonight and it's just a shame that he's not."

The sixth instalment of the saga sees wicked Lord Voldermort tighten his grip on the world of Muggles and wizards, and even Hogwarts is no longer the safe haven it once was.

Professor Dumbledore and Harry work to find the key to Voldermort's defences, enlisting the old wizard's friend Horace Slughorn to help with the task.

Other stars attending the premiere included celebrity chefs Gordon Ramsay and Jamie Oliver with their families, Clive Owen, Graham Norton and Gary Lineker.