Country star Toby Keith has cancelled all his planned meet and greet sessions due to "security concerns".

The Who's Your Daddy? hitmaker has just kicked off the U.S. leg of his Live in Overdrive tour, but the singer has decided to scrap all of his fan meetings.

A post on his website reads, "Due to current security concerns, all personal meet and greet requests for friends, family, and fan club members have been discontinued. Thank you for your understanding."

No further details were given.