Actor Nicole Kidman has been spotted for the first time since news broke of her separation and divorce after 19 years married to rocker Keith Urban.

The Oscar-winning actress, 58, was photographed hiking with her sister Antonia, 55, on trails near Kidman’s home in Nashville, Tennessee.

The tight-knit sisters appeared deep in conversation as they walked in the leafy outdoors for about 6.5 kilometres on Wednesday about 1pm (local time).

It was the day after Kidman officially filed for divorce in a Nashville courthouse on Tuesday (local time).

The Daily Mail published exclusive photos of Kidman, who was covered up in a baseball cap and oversized sunglasses, long-sleeved blue activewear jacket and black leggings.

Kidman was reportedly observed “gesticulating expressively” at times and also laughing.

At other moments during the walk Kidman linked arms with her sister and placed her hand on her heart.

Kidman has reportedly leaned heavily Antonia for support this year after separating from Grammy-winning country musician Keith Urban.

“Nicole’s sister has been a rock, and the entire Kidman family has come together to support one another,” a source told People.

In August, mum-of-six Antonia was with the Australian actress during the US summer holidays.

Kidman posted photos of herself with daughters Sunday Rose, 17, and Faith Margaret, 14, with Antonia also appearing in the pictures.

Antonia was with her sister during the US summer. Photo: Nicole Kidman

Kidman and Antonia are said to share a bond akin to twins and have been each other’s rock during life’s difficulties.

Antonia was also there for Nicole when Hollywood megastar Tom Cruise filed for divorce in 2001.

And Kidman was a shoulder to lean on during her younger sibling’s divorce from her first husband of 11 years Angus Hawley, who later died of a heart attack.

In September last year, their beloved mother Janelle died and the sisters came together in grief.

Kidman’s divorce documents filed this week state Kidman and Urban have undergone “marital difficulties and irreconcilable differences”.

Kidman and Urban, two of the biggest stars to come out of Australia in recent decades, have been red carpet fixtures throughout their two-decade relationship, with Urban joining his wife at the Oscars and Kidman attending music events like the Academy of Country Music Awards.

The filings include a marriage dissolution and childcare plan agreed on by the couple and submitted for a judge’s approval.

“The mother and father will behave with each other and each child so as to provide a loving, stable, consistent and nurturing relationship with the child even though they are divorced,” says the permanent parenting plan, using language common in the state’s divorces.

“They will not speak badly of each other or the members of the family of the other parent. They will encourage each child to continue to love the other parent and be comfortable in both families.”

The plan asks that Kidman be the primary residential parent to the couple’s two daughters, ages 17 and 14, having them for 306 days a year. Urban will take them for the other 59.

The girls have lived in Nashville, Tennessee, all their lives, and the documents give no indication that will change.

The filing states that each parent earns more than $US100,000 a month and neither will need childcare or spousal support.

The marriage dissolution plan lays out a roughly equal division of joint assets, with each keeping all the assets that are in their own name, including the copyrights and royalties for their artistic work.

The detailed agreements suggests that the divorce had been in the works for well over a month at the least. Urban signed the parenting plan on August 29, Kidman on September 6.

It will take at least 90 days for the divorce to become final under Tennessee law.

Representatives for Kidman and Urban did not respond to emailed requests for comment on Tuesday.

Nicole Kidman and Keith Urban at the US Open in 2023. Photo: AAP

Both raised in Australia, Kidman and Urban met in 2005 at a Los Angeles event honouring Australians and were married in Sydney the following year.

The marriage was the first for Urban and the second for Kidman, who was married to Tom Cruise from 1990 to 2001. Kidman also has two older children with Cruise.

The couple had publicly but lovingly described some marital difficulties, but there were still few, if any, signs they were headed for divorce. Media reports of their separation came just a day before the divorce filing.

Last year at the premiere of the Netflix series The Perfect Couple, Kidman told The Associated Press the term didn’t apply to her and Urban.

“You’re heading for trouble if you consider yourselves the perfect couple,” she said. “I’m not a believer in perfect.”

A few months earlier, Urban paid tribute to Kidman and brought her to tears when she received the AFI Life Achievement Award.

Urban said she showed him “what love in action really looks like” when his substance abuse problems emerged almost immediately after they wed in 2006.

“Four months into our marriage, I’m in rehab for three months,” Urban said. “Nic pushed through every negative voice, I’m sure even some of her own, and she chose love. And here we are 18 years later.”

Kidman’s film roles have included Days of Thunder, Eyes Wide Shut, Moulin Rouge and The Hours, for which she won an Academy Award for playing author Virginia Woolf.

She has more recently worked in television, including the series Nine Perfect Strangers and Big Little Lies, for which she won Emmys as both actor and producer.

Urban has been a major country star since the 1990s, with hits including Somebody Like You and Blue Ain’t Your Color. He has won four Grammy Awards and more than a dozen Academy of Country Music Awards.

-with AAP