Australian singers Troy Cassar-Daley and Adam Harvey have withdrawn their nominations for the upcoming Country Music Association of Australia (Cmaa) awards after veteran John Williamson declared them undeserving of the show's top honour.

The duo landed six nods, including a nomination for Album of the Year, for their Great Country Songbook collaboration, but the achievement was soured this week (beg09Dec13) when Williamson resigned as president of the Cmaa over claims the organisation's annual awards show has become too American.

He publicly criticised artists including Keith Urban for their American-style sound, and slammed Cassar-Daley and Harvey's inclusion in the Best Album nominations as the record is made up of U.S. song covers.

In an open letter, he writes, "The fact that it (Great Country Songbook) was even nominated blows me away. I feel that the organisation has got the wrong message and I don't want to be a part of it."

He adds of Urban, who is nominated in the Best Male Artist category, "There should be an award for international artists who do the American thing. He gets awards over there. Maybe we could give him an international award, but I don't think that should be recognised as Australian country music."

The rant has now prompted Cassar-Daley and Harvey to withdraw their nominations.

Harvey says of the decision, "It would have been awkward. I don't want the Golden Guitars to be about who didn't deserve to win or who shouldn't be there... To be honest, I have been hurt by some of the comments, not only from Willo (Williamson), but from others I thought were really good friends as more people weighed in on this debate. Our intentions in making this record were good and still are."

The singer also insists he is especially saddened by Williamson's stance as they previously earned a Cmaa nomination together for their cover of an American classic, Roger Miller's King Of The Road.

He adds, "John Williamson did ring me himself, so I'll give him that, and said he hoped he hadn't lost a friend over this but I had to tell him I was pretty disappointed. It was his idea for us to do King Of The Road and he was happy for that to be nominated. He told me he now regrets that."

Harvey concluded by defending Urban: "Keith Urban is proudly Australian and should be celebrated. Australia has a fantastic country music industry and I think there's plenty of room for all of us."