In a blistering encounter with federal parliamentary secretary for the environment Simon Birmingham on 2GB,  Mr Jones said Canberra's decision to approve the plan flew in the face of promises to preserve the heritage of the area for all Sydneysiders, which Mr Abbott had made as the local member in 1997.

"You have compromised the Prime Minister," Mr Jones railed. "He has not been properly informed, you have not done your homework on what commitments the PM has given when he was a member and now he faces a Julia Gillard moment because the exact opposite of what he promised ... [is] being done."

Mr Jones was referring to the former Labor leader's promise never to introduce a carbon tax, which she subsequently reversed. The veteran broadcaster waged a strident campaign against the tax, branding Ms Gillard "Ju-liar".

On Friday, Mr Jones challenged Mr Birmingham over the fact that the site, a former army transport depot and intelligence headquarters known as 10 Terminal, was in a bushfire prone area accessed by a single dead-end road.

One prominent fire consultant has warned that this renders it a potential "horror show" if elderly residents had to be evacuated in a hurry.

Fairfax has previously reported the NSW Rural Fire Service had not yet signed off on the suitability of the site for an 89-bed aged-care home , despite both the federal government and the Sydney Harbour Federation Trust - which has custody of the site - announcing approval of the plan on October 23.

But on Friday Mr Birmingham conceded  the project would not go ahead unless it got RFS approval.

"I'm saying we will rely on the NSW Fire Authority," Mr Birmingham said. " We will take their advice ... and this will stand or fall on whether it complies with their advice. That's an iron clad assurance."

Mr Birmingham could not explain why approval had been given in advance of an all -clear from the RFS, except to argue that the proposal had to be " finalised" before it could be assessed.

"You blokes have gone mad," Mr Jones said. "You should have checked all of that before you made an announcement."

It's the second time in a week that the Abbott government  has received a tongue-lashing from Mr Jones, the earlier criticism being over the China Free Trade agreement.

In a statement late on Friday the Sydney Harbour Federation Trust said it had based its original approval on the advice of  another bushfire consultant.

"Consultation with the NSW RFS is ongoing and Senator Birmingham's remarks reflect our commitment to adhering to their requirements," a Trust spokesman said.