Mark confirmed the couple's break up in an interview with The Mirror, claiming the pair's 'busy schedules' had influenced their decision to call time on their romance, but he and Leah have remained friends.
Mark said: "We are both incredibly driven people and, due to our busy schedules, the relationship just wasn't working, so we decided to go our separate ways."
He added: "Leah is a lovely girl, and we remain good friends."
A rep for Leah also confirmed the split to Reveal, but had no comment to make.
She and Mark had reportedly started dating in December last year. They first confirmed their relationship in January, by sharing holiday photos with each other during a romantic break to Mexico.
At the time news of their romance surfaced, reports claimed that the pair were concerned over what Lord Alan Sugar would make of their relationship, as they are both business partners to him.
While Leah won The Apprentice in 2013, Mark bagged himself the winning title and the opportunity to team up with Lord Sugar the following year in 2014.
Leah opened her first cosmetic procedures clinic in Central London with Lord Sugar's £250,000 investment and has since opened another in Loughton, Essex. Australian born Mark used his investment to build his digital marketing business, Climb Online.
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