The 25-year-old's involvement in the three-week long competition will rule him out of most of Leeds' January fixtures, increasing the urgency of the club's search for new midfielders in next month's transfer window.
United manager Simon Grayson was likely to strengthen that area of his squad regardless of Kilkenny's international commitments but the prospect of losing Kilkenny to the Asian Cup for the best part of a month has heightened the need for fresh signings.
The former Birmingham City trainee featured in a provisional 50-man squad selected by Australia coach Holger Osieck two weeks ago, and he is understood to have made the final cut.
An official announcement from Football Federation Australia was expected today and Kilkenny is due to link up with the national squad after Leeds' game against Middlesbrough on Saturday afternoon.
He will miss United's trip to Cardiff City on January 4 and their FA Cup third-round tie at Arsenal four days later.
Australia have arranged a friendly with the United Arab Emirates on January 5, two days before the Asian Cup begins.
The Socceroos' first group fixture against India takes place on January 10 and they will wrap up their group campaign against Bahrain on January 18.
The tournament does not conclude until January 29, 48 hours before Leeds' trip to Hull City.
United are due to play a total of five matches during January, including four Championship games, and the impending departure of a key midfielder is a significant blow for Grayson.
Kilkenny has appeared in all but two of United's league fixtures this season, helping the club climb to second place in the Championship ahead of their Boxing Day clash with Leicester City, and uncertainty exists over the immediate future of other midfielders in Grayson's squad.
Bradley Johnson has been on the transfer list at Elland Road since the end of November and is likely to be sold in the January window.
Veteran Senegalese international Amdy Faye is rapidly approaching the end of a short-term deal which runs until the start of next month.
Kilkenny is himself out of contract with Leeds at the end of the season having so far failed to agree an extension to his deal but his call-up for the Asian Cup is an opportunity to strengthen his international prospects.
Australia included Kilkenny in their squad for the 2008 Olympic Games but he has been on the periphery of the Socceroos' senior side for the past two-and-a-half years.