The Federal Government will abolish certificates that give ministers sweeping powers to keep documents a secret as the first step in reforms to the Freedom of Information law.

Cabinet Secretary John Faulkner announced cabinet had agreed to abolish conclusive certificates, and legislation to do that will be introduced later this year.

But Mr Faulkner revealed that more broad ranging reforms to the FoI Act will not come into force until next year, after the original deadline his office imposed of the end of this year.