The Academy of Country Music Awards took place in Las Vegas, but the biggest fashion statement of the night was made 1,500 miles away. And given the way things have been going for the past three months, maybe it's not so surprising that the statement was made by Natalie Maines of the Dixie Chicks.

Maines sported a shirt emblazoned with the letters "F.U.T.K." while the trio performed "Godspeed (Sweet Dreams)" via satellite from a concert in Austin, Texas. The special segment was part of the ACM Awards show televised live from Las Vegas. Later in the show, Vince Gill opened the envelope to learn that Toby Keith had been named entertainer of the year and said, "Well, I think his name was on somebody's shirt tonight."

Maines' shirt became a hot topic on radio talk shows and Internet message boards, thanks to previous comments she has made about Keith and President George W. Bush. After experiencing a backlash from fans and radio over a comment she made about Bush during a London concert in March, Maines wore a shirt carrying the message "Dare to Be Free" when the U.S. leg of the Dixie Chicks world tour kicked off earlier this month in Greenville, S.C.

When asked if Maines intends to explain what the letters "F.U.T.K." meant, a publicist at Front Page Publicity -- the firm responsible for the Dixie Chicks' media relations -- told CMT.com Friday (May 23), "I don't know."

Assuming that the last two letters of the acronym refer to Keith, it's easy to speculate the meaning of the first two. And if that's the case, then Maines' shirt appears to be another jab in a dialog that began almost a year ago when she criticized Keith's flag-waving song, "Courtesy of the Red, White and Blue (The Angry American)." On the other hand, Chicks supporters on Nashville's Music Row have offered a kinder, tongue-in-cheek definition of "F.U.T.K." -- "Friends United in Truth and Kindness."

Following Wednesday's (May 21) ACM Awards, Keith traveled to Los Angeles for a Thursday appearance on the ABC late night talk show, Jimmy Kimmel Live. Keith said he doesn't know what the letters on Maines' shirt meant. "I have no idea," he said. "It happened during the [ACM] show when I was already gone."

With several members of Kimmel's audience wearing shirts with the letters "F.U.D.C.," Keith explained the history of what has become a public feud.

"She attacked me about nine months ago over the 'Angry American' song," Keith said. "I took the high road for a little bit and then she didn't think that she got the fight, I think, that she wanted. So then she attacked our president on foreign soil and got the fight she wanted, I guess." Keith added, "She's still not done. If y'all think she's done, you're crazy. Stuff comes out of her blowhole daily."

Keith may disagree with Maines' comments, but he likes their music. However, he also expressed concern for the other members of the Dixie Chicks -- Martie Maguire and Emily Robison.

"They make great music," he noted. "I think it's too bad for the other two that … it has to be what it is, because they do make great music."