Sweden, Russia and Italy are among the favourites to win the 60th annual Eurovision Song Contest, which takes place in Vienna later.

A record 27 countries will take part, including Australia, which has been invited to compete for the first time to mark the diamond anniversary.

Australia's Guy Sebastian is one of the country's biggest stars and is also hotly tipped for the Eurovision title.

Guy Sebastian won the first Australian Idol competition in 2003. Photo: Reuters/BBC

Swing duo Electro Velvet will fly the flag for the UK.

"We just can't wait to get up there," singer Bianca Nicholas said on Friday. "The nerves are starting to come a little, but that's a good thing. It just means that you care a lot about it."

Her singing partner is Alex Larke, whose main claim to fame to date is impersonating Mick Jagger in The Rolling Stones tribute band The Rolling Clones.

The pair will sing I'm Still in Love with You and are fifth on the running order for Saturday's final at the Wiener Stadthalle stadium.

Around 200 million viewers are expected to tune in to the event on television.

Sweden's Mans Zelmerlow has long been considered the frontrunner, followed by Russia's Polina Gagarina and Italy's pop-opera trio Il Volo.

Sweden's Mans Zelmerlow is regarded as the frontrunner. Photo: BBC

Conchita Wurst took the crown for Austria last year, and it is tradition for the winners to host the competition the following year.

Earlier this week, Ireland, the most successful country in Eurovision history, went out of the competition after failing to make it through the semi-final.

The seven-time winners couldn't muster enough votes for their youngest ever entrant, 17-year-old Molly Sterling.