John Key is being accused of deliberately misleading the public on the matter of jihadi brides.

The Prime Minister has admitted to the Green Party he knew no women had left New Zealand to fight in the Middle East, six months before he first raised the idea.

The Greens said Mr Key knew no women had left from New Zealand in May 2015, prior to introducing the notion of Kiwi jihadi brides at a December select committee hearing.

SEE ALSO: Kiwi women heading off to join ISIS, Key insists

Green Party co-leader Metiria Turei said the Prime Minister purposely spread incorrect information.

"He had information that one woman had left from another country, but not that any New Zealand woman had left from New Zealand."

Ms Turei said John Key lied by omission and that's not good enough. She said he should be providing the country with accurate information.

"We're now in a situation where we can't believe the SIS. They didn't provide the information, and we can't believe the Prime Minister and what he says either."

SEE ALSO: Govt's 'jihadi brides' claims raising unnecessary alarm