Just a week after proclaiming their love for one another, Nicole Scherzinger and Lewis Hamilton have reportedly split up.

Their busy work schedules to blame, the pair decided they couldn't carry on with their long-distance relationship.

Only last week, Formula One star Hamilton hinted that he could soon propose to the former X Factor judge.

"We've been together for five years, which is quite a milestone really," he's quoted by The Sun as saying.

"But hopefully in the near future [he will propose]. Maybe before we get to six years."

The couple just celebrated their five-year anniversary. 

This morning, the paper has reported that the couple have split up.

"It’s so hard to keep up a relationship when they’re barely in the same country as each other. Both have supported each other in their careers and will continue to do so," a source said.

Nicole and Lewis found the long-distance relationship difficult. 

The couple began dating in 2007 after meeting at the MTV Awards.

They first split up in January of 2010, before getting back together four months later.

They broke up again in the autumn of 2011 before deciding they'd give it another go.

We'll keep you updated...