Cara Delevingne plays Elton John in Step Into Christmas video ...

Model and actress Cara Delevingne has taken on the role of Elton John in a new video for his song Step Into Christmas.

In a reimagining of the 1973 track's original video, Delevingne dons oversized glasses and a colourful waistcoat – striking an uncanny resemblance to the music legend.

The model said playing the 77-year-old musician was "a dream I didn't know I had until it happened".

"I wish I could pretend to be Elton every day."

More than 50 years since the original, Wednesday's recreation takes viewers behind the scenes as producers try to make the set suitably festive.

It opens as Delevingne, in full costume including a wig, tells unimpressed producers that she will be playing Sir Elton.

Switching between near-identical shots of the two videos, the model sings along to the iconic Christmas tune while playing the piano, imitating Sir Elton's original moves.

Sir Elton said he had seen Delevingne at Glastonbury music festival over the summer, where the pair had discussed how they would love to work together "if the right idea came up".

"She's hilarious to spend time with, we both have quite a self-deprecating sense of humour," Sir Elton said.

When the idea of Delevingne playing him in the original music video came along, the pop star said it was "the perfect opportunity".

"Thank God Cara thought the same, because it came out great."

Delevingne, 32, said Sir Elton had "always been an idol of mine".

"To say his music has had a deeply profound effect on me is an understatement.

"I hope that Elton may one day return the favour and agree to play me in my not yet developed, written, pitched or funded biopic. Fingers crossed."

Step Into Christmas reached number 24 in the UK top 40 on its release in November 1973, and the top of the Billboard Christmas Singles chart in the US.

The song is currently number 15 in the UK singles chart.

Last month, Sir Elton said he has been unable to finish his new album due to his vision issues.

He told ABC's Good Morning America he lost his vision in his right eye due to an infection and his left eye "is not the greatest".

"I can do something like this [interview] but going into the studio and recording, I don't know, because I can't see a lyric for start," the singer said.

But on The Late Show with Stephen Colbert on Tuesday, Sir Elton said he was still going to make records and have a "musical future".