Cabinet minutes should be "absolutely protected" from Freedom of Information requests, the government's former security co-ordinator has told the BBC.
Sir Richard left government at the end of last year
Sir Richard Mottram said releasing them would not be good for government debate as people would be more cautious about what was being written down.
It follows a ruling by the information commissioner that minutes relating to the Iraq War should be released.
Sir Richard said the minutes would not be as revelatory as some thought.
The government was told to release minutes of two cabinet meetings in the days before the Iraq war by Information Commissioner Richard Thomas. It had initially rejected a Freedom of Information request.
Former Joint Intelligence Committee chairman Sir Richard told BBC Radio 4's World at One that he respected the commissioner, but felt his decision had been wrong.
"I personally think that cabinet minutes should be absolutely protected," he said.
"Once there's a risk they are going to be disclosed ... I think this will drive the system to be even more cautious about what's written down."
He added that disclosing cabinet minutes "is not helpful for the long-term health of debate inside government and effective cabinet government."
And he said he doubted the Iraq minutes would be "quite the revelation people think".
The Cabinet Office had refused to release minutes on the grounds that the papers were exempt from disclosure.
The information commissioner said in his ruling he did not believe that disclosure would "necessarily" set a precedent in respect of other cabinet minutes.
In his interview with the BBC, Sir Richard also said that the government's upcoming national security strategy would make clear that there are other risks to the public which are equally or more worrying than terrorism.
He mentioned climate change and a global flu pandemic, which he thought "highly probable" - and said the emphasis on the strategy would be in engaging citizens in terms of what they can do to counter those risks.