Work on a fence around Parliament House is well underway, despite concerns voiced by the public and architects, a committee has heard.
Much of the perimeter of Parliament House will be protected by a 2.6 metre high fence.
Department of Parliamentary Services secretary Robert Stefanic told an estimates committee on Monday a proper tender process had been completed, but he admitted there was no public consultation.
Mr Stefanic said the key advice came from the Australian Federal Police, ASIO, the attorney-general's department, finance department and his own department.
Contrary to media reports it would not be a fence right around the building.
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"There are a number of fences at strategic points," Mr Stefanic said.
"There will be still substantial space on northern ramps for the public to walk up and down or roll down."
A third of the grass ramp area would remain accessible and members of the public would be able to access the rooftop via internal lifts.
Mr Stefanic said he had met with the architects association and it had retracted an online petition against the changes after being briefed on the plans.
No further "invasive" measures would be needed into the future, even if there was an escalation in the national security threat level.
Senator Parry told the committee there was never any plan for a "moat" around Parliament House.
"There was going to be ... a ditch called a 'ha-ha'," he said.
That was mooted for one section of Parliament House perimeter on one boundary, but that had some serious technical difficulties.
"It was not a moat, not around Parliament House, never to be filled with water or crocodiles or anything like that - it was simply going to be a ditch to prevent people from accessing the ramps."
