New Zealand First leader Winston Peters has criticised the way in which investigative journalist Nicky Hager released his book Dirty Politics so close to September's general election.
The book came out a month before the election.
Mr Peters told Radio New Zealand's Sunday Morning the book was devastating for the Government but the information should have been drip-fed in small, consumable amounts to the public.
"The book itself came out with a full disclosure at one time," he said.
"He gave his opponents time to fudge the issue, to do the, sort of, the classic, the squid approach - murky the waters so people will start to believe their defences."
Mr Peters said he was not criticising Mr Hager's integrity but the naivety of the launch timing.