The hip-hop star and his reality TV star girlfriend have rarely been apart since they began dating earlier this year.
On Wednesday, Kim jetted into London to launch her Kardashian Kollection clothing line with her sisters Kourtney and Khloé. Although Kanye didn't accompany her on the flight from Miami, he was spotted walking into her hotel in the early hours of this morning.
It's thought he took the long journey for no other reason than to be with his girlfriend.
Kim has also proved how much she loves the hip-hop star, having been seen out rocking a gold ring bearing the initial KW yesterday.
Their behaviour has added fuel to the rumours they are planning to get engaged. It's been suggested Kim was expecting Kanye to propose when they went on holiday to Venice to mark her 32nd birthday recently.
The ring didn't materialise, apparently because Kanye is reluctant to pop the question while Kim is still technically married. She is in the process of divorcing Kris Humphries, who she was married to for just 72 days before their split.
Those close to the pair are adamant they will be taking things to the next level before too long.
"They really have connected with each other. It's so much more than the obvious, physical attraction," one source told Chicago Sun-Times. "When you're around them you just get it. Their chemistry is so tangible you can practically touch it."