The American reality TV star took in the famous sites of the capital on Saturday (14 December), including Big Ben and Hyde Park, on what was apparently another rendezvous with British born Harry.
In one Instagram snap, Kendall can be seen admiring her view of London while appearing to be wrapped up in a cosy coat.
She captioned the photo: "hey Ben!"
It is thought 18-year-old Kendall whizzed to our shores to see Harry after he had attended the NRJ Music Awards in Cannes, France, with his One Direction bandmates on Saturday night.
The superstar boy band collected two awards at the prestigious ceremony, but it seems Harry's mind was elsewhere, as he dashed back to London that same evening and was caught outside Kendall's hotel at 2am.
The 19-year-old singer was seen looking suave in a pair of skinny black trousers, a red checked shirt and a black blazer.
Making an effort for the Kardashian sister?!
However, their rumoured meeting didn't last too long, since Harry later got back to work and performed with One Direction on the X Factor final, while Kendall jetted back to LA to reunite with her family.
The twosome are thought to be dating after being seen leaving a dinner date in LA last month and then being mobbed by fans outside a hotel in New York.
Although neither star has confirmed the romance reports, Kendall did also tweet on Saturday: "lots of love!!"
Hmm, could that be an indication that she's falling for a certain someone?
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