One of Australia's most celebrated celebrity couples, Nicole Kidman and Keith Urban, have called it quits after almost 20 years of marriage, according to media reports.

The Oscar winner and her country music hit-maker husband have reportedly been living apart since June, entertainment website TMZ first reported.

"Sometimes relationships just run their course," an unnamed source close to the couple told the New York Post, confirming the split.

In June, Kidman, 58, shared a photo of herself cuddled up to Urban on Instagram to celebrate their wedding anniversary.

Four-time Grammy winner Urban, 57, has moved out of the couple's Nashville home, according to the reports, with claims Kidman was desperate to save the relationship.

"She didn't want this," another source told People magazine.

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