Stars arrive at Oscars red carpet

Designer-clad movie stars lit up the Oscars red carpet ahead of the 81st Academy Awards.

An overcast afternoon burst into technicolour in the streets surrounding the Kodak Theatre, with the stars of Bollywood-infused best picture favourite Slumdog Millionaire among the early arrivals and stealing the show.

The film's British director Danny Boyle was seen accompanying child actors from the film, who were flown to Los Angeles for the ceremony, a world away from their lives in Mumbai's shantytowns.

Ayush Mahesh Khedekar, who plays the film's hero as a child, told a reporter delightedly: "It's unbelievable. I never thought I'd be at the Oscars."

Meanwhile, three of the film's adult stars Dev Patel, Freida Pinto and Bollywood legend Anil Kapoor were drinking in the moment.

"I'm not the man of the hour but it's amazing," said the London-born Patel. "I can't wait to see some of these stars walking down the red carpet."

Kapoor, meanwhile said he was "overwhelmed" by the experience.

"I'm really so grateful to all the people around the world who have held hands to make this film what it has become," Kapoor told E! television.

Kapoor meanwhile mischievously fuelled rumours of off-screen romance between Pinto and Patel. "There is a potential and they look great together," he said.

Other celebrities including teen idol Miley Cyrus and Milk star Emile Hirsch were among the early arrivals.

Cyrus, best known as the 16-year-old star of Disney's Hannah Montana television show, arrived with her mother in tow and said she was looking forward to star-spotting.

"I'm just hanging out and star-stalking," she quipped to E! television reporter Ryan Seacrest. "I want to see Angelina Jolie. She could adopt me if she wants to."

Meanwhile, Hirsch, who has a key role in gay rights biopic Milk, arrived in a traditional black tuxedo notable for having a white ribbon pinned to a lapel, a symbol of support for same-sex marriage.

The Oscars red carpet arrivals took place under blanket security, with police helicopters hovering overhead and marksman positioned on building surrounding the awards venue.

Tension cranked up a notch as two accountants from PriceWaterhouseCoopers arrived carrying a briefcase bearing the envelopes with the names of this year's Oscar winners.

The Oscar ceremony starts about midday (AEDT).