Rob Kardashian and Rita Ora
Reality TV star Rob Kardashian declares his love for singing sensation Rita Ora Reuters

Reality star Rob Kardashian has declared his love for rumoured love interest Rita Ora on Twitter.

Kim Kardashian's younger brother fuelled mounting speculation that he is in a relationship with singer Ora after posting a romantic message on the social networking site.

After Ora celebrated her debut single R.I.P making it to number one in the British singles chart, Kardashian reportedly jetted into London to help her celebrate.

Despite the couple avoiding being photographed together, Kardashian was more than happy to share his pride with fans.

Heading to Twitter, he posted a snap of Ora celebrating alongside with the caption: "That's MY baby! You did it. I love you and you're my wife."

Kardashian, 25, later tweeted to fans: "I love my woman! I'm so proud of you!"

Ora, 21, sent tongues wagging when she arrived at the London nightclub Whisky Mist dressed in a daring slashed leather dress.

Former Dancing With the Stars contestant Kardashian went for a more causal look, with a hooded denim jacket and white trainers.

According to reports, the couple were introduced to each other by a mutual friend last year.