Kristen Wiig impersonates Harry Styles

Kristen Wiig blew crowds away with her Harry Styles impression last night.

The American funny woman looked uncannily like the One Direction heartthrob when she dressed up as Harry for a spoof interview on The Tonight Show Starring Jimmy Fallon.

The 40-year-old actress was dressed in black skinny jeans, a white deep v-neck T-shirt and a black tight fitting blazer, with the collar turned up.

The look was finished with some long chains, and Harry's trademark coiffed hair.

"I'm from England," Kristen told Jimmy in her normal accent.

"We were at school, and it was one of those, 'Hey, I sing' and then everyone was just like, 'Let's go to Harry's house and just start rehearsing' and then we sent a tape to RCA. And they called my house.

"[The number] was in England, so it was very long. And they were like, 'Yeah, do you want to be on out record label?' And we were like... I was really freaked out," she explained when asked how the band had formed.

She agreed with Jimmy when he told Harry he was now so famous, and then went on to talk about his beauty regime.

Harry is instantly recognisable with his laidback, rock infused style. His wavy hair is probably his best known feature, and Kristen commented that it took two hairdryers to get it just right.

When Jimmy asked how the name One Direction came about, Kristen revealed to the audience that the boys were united in their singing ambitions.

"We just feel like we want to, like, sing about positive things and juts keep everything moving forward. I mean I've said this like a lot in other interviews," she dismissed.

Jimmy took over as the host of The Tonight Show on Monday evening, replacing Jay Leno.

During his Rapid Fire Round he shot questions and Kirsten to answer in quick succession.

She confessed that green was Harry's favourite colour, giraffes are his animal of choice and Denzel Washington takes the crown as his favourite actor.

Before treating the crowds to a rendition of What Makes You Beautiful, Kristen signed a poster to Jimmy from 'Harry Stiles'.

The audience roared with laughter as Kristen and Jimmy performed an out of tune duet, before the charade came to an end.