Video footage of New Zealand pop star Lorde performing in a battle of the bands talent contest has surfaced online.

Lorde, as the frontwoman to a band, Extreme, sings songs by Richard Blackwood and The Cult at the event held at Auckland's Belmont Intermediate School. The group would go on to finish third in the competition. 

Lorde says during the competition:

"We’re gonna start with a bit of classic rock from Richard Blackmore’s Rainbow."

This week it was also announced that Lorde had signed a £1.56 million ($2.5m) publishing deal with Songs Music Publishing. The company's president Ron Perry told Billboard: "She's going to be a really big songwriter outside of Lorde. She's going to have a lot of big songs out there as Ella (Yellich O’Connor), she's a once-in-a-generation type artist."

The teenager, now 17, was originally handed a development deal by Virgin Records after seeing a video of her performing at another school talent school. Earlier this year, she released her debut album 'Pure Heroine', reaching No. 4 in the Official UK Albums Chart, whilst her single 'Royals' hit the top spot in the Official UK Singles Chart. 

Meanwhile, in the States the track topped the charts for a sixth week this week. She is the youngest female chart-topper in 25 years and also the first person from New Zealand to score a US number one. 

Lorde also recently unveiled a preview of her cover for Tears For Fears' 'Everybody Wants To Rule The World', which will feature on the forthcoming The Hunger Games: Catching Fire soundtrack.

Watch 12-year-old Lorde sing, and listen to her recent version of 'Everybody Wants to Rule The World' below: