From New York to St Pancras International Station, Alicia Keys surprised travellers earlier today (December 11) as she played some classic hits on Sir Elton John's piano.

The 42-year-old singer took a seat at the legendary piano and performed Empire State Of Mind, Ain't Got You, No One and her latest single Lifeline.

Videos of the US star have flooded social media showing countless phones in the air recording the performance from the Grammy Award-winning artist.

Alicia arrived at the station after performing during the second night of Capital’s Jingle Bell Ball with Barclaycard at the O2 Arena in the city on Sunday (December 10).

Watch Alicia Keys perform Empire State Of Mind at St Pancras International Station

The caption of this TikTok video posted by user @flett.ken said: “Amazing when your #emr train runs late and you get @Alicia Keys live to start your day @St. Pancras International #aliciakeys.”

@flett.ken Amazing when your #emr train runs late and you get @Alicia Keys live to start your day @St. Pancras International #aliciakeys ♬ original sound - Ken Flett

Dressed in a leather biker jacket, black skirt and knee-high boots, Alicia stunned the gathering crowds with her powerful vocals.

Commenting underneath the clip, one user praised Alicia, saying: “Her voice is amazing .. no mic either or auto tune.”

“Why does nothing like this happen when I’m at St Pancras,” asked another.

It seemed to be quite a moment for some commuters, as one person noticed: “That guy without the phone fell in love.. so cute.”

Sharing their thoughts, this TikTok account wrote: “I’d cry if I saw this live I’d be bawling.”

What is Sir Elton John’s piano at St Pancras International Station in London?

The black Yamaha piano was gifted by Sir Elton after he performed at the station back in 2016.

The gift coincided with the release of his 30th studio album titled Wonderful Crazy Night.

Posting on his Instagram after his musical performance at the time, he said: “Surprise!! I popped into St Pancras International to christen the Yamaha piano which I donated to the station.

"Now everyone can have a play.”