Miley Cyrus and Cody Simpson have split up.

Miley Cyrus

Miley Cyrus

The former couple reportedly decided to end their relationship after 10 months of dating a few weeks ago, though it is unclear why they decided to break up.

Sources told E! News that 'La Da Dee' hitmaker Cody was the one who called off the romance.

News of the split will come as a shock to fans as it was only in July that it was reported the 'Nothing Breaks Like a Heart' singer and the 23-year-old pop star were "doing great together" and had enjoyed dividing their time between California and Nashville while quarantining amid the coronavirus pandemic.

A source said recently: "Miley feels very secure with Cody and really trusts him.

"He treats her well and makes her feel like a million bucks.

"Cody and Miley have been quarantining together this entire time and are very happy. They are both low-key and enjoy doing simple things like hanging out at home, watching movies and cooking."

And the 27-year-old star's decision to quit drinking at the beginning of this year was said to have helped their relationship.

A source previously said: "Miley's sobriety has made her very present in her relationship. Her decision to be sober has changed the way she thinks about life.

"She would describe herself as a believer in this new way of life and is looking to make sobriety a long-term lifestyle."

The former couple got together in October 2019, shortly after Miley's brief fling with reality TV star Kaitlynn Carter - who she struck up a romance with after the breakdown of her marriage to Liam Hemsworth - came to an end.

Miley and Cody were close friends before their bond turned romantic but it's currently unclear how amicable things are between them.