Tim McGraw jokingly sledges Keith Urban and Nicole Kidman

Country superstar Tim McGraw has opened up about his marriage to fellow singer Faith Hill before roasting Aussie couple Keith Urban and Nicole Kidman as “unattractive”.

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Country music’s most enduring couple Tim McGraw and Faith Hill have a simple rule to keep their marriage strong.

McGraw, however, will break that rule of never being apart for more than three days when he heads to Australia next week.

“Faith and I have had a three-day rule for the longest time,” McGraw said.

Singers Tim McGraw and Faith Hill at The Grammy Awards. Picture: Frazer Harrison

“Rarely have we gotten outside of that. There has been a handful of times that it has been a week, or 10 days at the most, so this will be 10 days apart and it is actually our 23rd wedding anniversary so it is the first time I have missed an anniversary.”

Similarly, Keith Urban and Nicole Kidman have a similar rule: they spend no more than a couple of weeks apart at any given time pursuing their busy careers.

McGraw, 52, and Hill, 51, have three daughters and live in Nashville.

Hill (left) with Nicole Kidman. Picture: M. Spencer Green

Taylor Swift is joined on stage by Keith Urban and McGraw at the CMA festival. Picture: Dean Chapple

He will headline the annual C2C concerts in Australia, playing Sydney’s Qudos Bank Arena on September 28 and the Brisbane Entertainment Centre on the 29th. He will also play the Deni Ute Muster, and two side shows — the Hunter Valley’s Hope Estate on October 4 and Melbourne’s Rod Laver Arena two days later.

“I will have to find something cool in Australia to make it up,” he said of missing his anniversary.

The multiple Grammy Award-winning singer is actually close friends with Urban, who he describes as ”one of the nicest people in the business”.

“It is just too bad that Keith is just so not attractive,” he joked.

“They are just such an unattractive couple (Urban and Kidman) so they have to be so talented to make up for it.”

Faith Hill and Tim McGraw have been married for 23 years.

More seriously, he added: “To see him continually experiment and to continually grow as a musician and, man, he just plays the fire out of that guitar. If I could play guitar like him, I would never sing another note.”

McGraw is working towards the release of his 15th solo studio album in 2020 and will play a number of new tracks in Australia.

“It paints a picture of the stages of life and the tapestry of life people go through,” he said of the new music.

“I don’t want to give too much away, but each section of the album paints a picture or a scene of a time in your life.”

Originally published as Tim McGraw jokingly sledges Keith Urban and Nicole Kidman