LOS ANGELES, Oct 1 — Nicole Kidman has officially filed for divorce from Keith Urban, ending a nearly two-decade marriage that had long been considered one of Hollywood’s most enduring unions.

The Oscar-winning actress, 57, made the filing in Tennessee on Tuesday, citing “irreconcilable differences,” the BBC reported today. 

Kidman and Urban, also 57, have been married since June 2006 and share two daughters: Sunday Rose, 17, and Faith Margaret, 14.

A source told gossip site TMZ that the couple, who had been living apart since the summer, were already on separate paths — and that while Urban was ready to move forward, “Nicole did not want to split.”

The filing comes as a shock to fans who have watched the pair navigate both triumphs and struggles together. 

Shortly after their wedding, Urban entered rehab for substance abuse, following an intervention led by Kidman and close friends. 

At the time, the singer credited his wife with helping to save both his life and their marriage.

“Everything was just designed, I believe, for that moment to fuse us together,” Urban said in a 2010 appearance on The Oprah Winfrey Show. 

“I look back now and realise Nic has taught me so much and brought so much into my life and opened my eyes in so many ways. [This is] the best place I’ve ever been.”

Despite rumours of strain, Kidman and Urban continued to make joint appearances in recent months. 

They were photographed in May at the Academy of Country Music Awards, where Urban received the ACM Triple Crown Award, looking affectionate and holding hands. In June, they were spotted cheering together at a Fifa Club World Cup match in Nashville.

Kidman was previously married to Tom Cruise from 1990 to 2001, with whom she shares two children.