Tim Mcgraw and Faith Hill's song which Ed Sheeran co-wrote has been hit with a copyright lawsuit.

'The Rest Of Our Life', which was a huge hit around the world last year, could cost everyone involved $5 million in damages after Australian musicians Sean Carey and Beau Golden have alleged that the track is a rip off of their song 'When I Found You', which they penned for Jasmine Rae in 2014.

Also listed in the legal documents are Ed's co-writing team - Johnny McDaid, Steve Mac and Amy Wadge.

According to The Hollywood Reporter, the suit states: ''The copying is, in many instances, verbatim, note-for-note copying of original elements of the Song, and is obvious to the ordinary observer.''

It will be the second time Ed faces lawyer, Richard Busch, who is representing the pair.

The chart-topping singer was sued by songwriters Thomas Leonard and Martin Harrington in June 2016, with the duo claiming Ed's hit single 'Photograph' had a strikingly similar structure to their track 'Amazing', which was released by Matt Cardle in 2012.

The songwriters argued in court that the tracks shared 39 identical notes, with similarities ''instantly recognisable to the ordinary observer''.

However, papers were filed dismissing the case with prejudice, with a California federal court reportedly enforcing the terms of the settlement.

However, Busch had refused to comment on the precise terms of the agreement.

Last year, Matt took to Twitter to clarify he was not involved in the lawsuit and to express his admiration for Ed, saying the 26-year-old star was a musical ''genius''.

Matt, who was the UK 'X Factor' winner in 2010, wrote: ''Please read news articles closely. This is not my lawsuit. I think Ed Sheeran is a genius and 100 percent deserves all his success.''

Meanwhile, in 2015, Robin Thicke and Pharrell Williams were ordered to pay $7.3 million in copyright infringement due to similarities between their number one single 'Blurred Lines' and Gaye's 'Got To Give It Up'.