MetLife Inc's long-term share buyback plans are uncertain and depend on how the regulatory environment develops in coming years, the company's chief executive said on Thursday.

"I don't have total confidence" in the ability to buy back shares over the next few years, Steve Kandarian said on a year-end investor call. MetLife's operating plans assume no buybacks in 2013 but some volume of share repurchases thereafter.

(Reporting By Ben Berkowitz; Editing by Gerald E. McCormick)