ISTANBUL (Reuters) - OPEC Secretary General Mohammed Barkindo said on Tuesday that any deal to freeze oil production was likely to last an initial six months and then be reviewed.

"The overwhelming majority of views, both within OPEC and non-OPEC, are looking at about 6 months and then to be reviewed," Barkindo told reporters on the sidelines of the World Energy Congress in Istanbul.

(Reporting by Parisa Hafezi and Rania El Gamal; Writing by Nick Tattersall)