A stunned Boris Johnson was left muttering “it’s a small world” after bumping into a Streatham Vale co-star from his recent cameo on Eastenders.

Just hours before nine million people tuned in to watch the Mayor pop by the Queen Vic for a pint, 41-year-old Elaine Smithers crossed paths with London's leader at the opening of a new library in Mitcham.

The Greyhound Terrace resident, who played Mr Johnson’s personal assistant during the episode, was astonished when the Mayor not only recognised her but made an effort to say hello.

She said: “I think he was actually quite shocked to see me and asked what I was doing here!

“It was equally surprising for me - the scene was filmed some time ago so I’m amazed that he remembered who I was. It took a while, but he looked at me in a confused way and then realised.”

It was the second time the Mayor had shocked part-time actress Ms Smithers as she had no idea who her co-star would be during the episode shot more than 10 weeks ago.

She added: “I was only told there was a chance someone special might be appearing before eventually finding out it was Boris.”

Mr Johnson said: “What an incredible coincidence. I guess it just goes to show what a small place London really is.”

The Mayor was in Mitcham to officially open Pollards Hill library which has recently undergone a £1m transformation following a successful National Lottery funding bid.

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