Known for their songs "I'm a Believer" and "Daydream Believer," the band outsold The Beatles and The Rolling Stones in 1967.
Original Monkees members Micky Dolenz, Davy Jones and Peter Tork embarked on a 45th anniversary tour earlier this year, but announced Tuesday the rest of their scheduled gigs, including dates in the United States and United Kingdom, had been scrapped, the BBC said.
"I am disappointed but the situation was unavoidable and I want to apologize to all the fans," Dolenz said in a statement on his Facebook page. "The Monkee Tour has, indeed, been canceled but for reasons that I cannot discuss at this time. I can say that the reasons pertain to business and are internal matters."
"I can only say that it has to do with business matters," the BBC said Tork wrote in a statement on his Facebook page. "I sincerely regret that it is not possible to continue this wonderful tour. I especially regret the inconvenience to those of you whose plans have been disrupted. Thank you for all your love and support. I hope to see you on the road sometime."