The move will put pressure on cultural institutions that control their own parking to decide whether they will allow their car parks to be flooded with commuters when pay parking begins next July.

As reported on Thursday, the Australian War Memorial will install sturdy barriers and boom gates to keep out commuters who now park there and ride or walk to Civic.

Veterans, tourists and staff will be given vouchers for free parking.

One option being investigated by cultural institutions is a version of the honesty-based voucher system that operates at the National Portrait Gallery.

The gallery usually does not open its public car park until 9.45am to discourage workers from other places arriving early and momentarily pretending to be interested in the gallery's exhibitions to have their parking fee cleared.

Along with Parliament House, the four independent institutions that control their own car parks - the National Gallery, National Portrait Gallery, High Court and War Memorial - face a dilemma: impose paid parking or a voucher system on staff and volunteers or risk having free car parks swamped by public servants.

The Portrait Gallery expects to make a decision this year on whether to keep or modify its ticket validation system or adopt a different scheme. ''The board is considering the options but for us, the most important thing is the interests of our visitors to the portrait gallery and they will be at the forefront of any decision taken by the board,'' a spokeswoman said.

The National Gallery of Australia is considering a voucher system as one of its options.

''The gallery aims to introduce pay parking arrangements consistent with government policy and the proposed parking fees across the parliamentary zone from 1 July 2014,'' a spokeswoman said.

''This allows the gallery to control access to the car parks and manage the hours of operations to ensure parking is available for visitors, guides and volunteers.''

The High Court and Parliament House are still considering how to respond to the budget decision to introduce pay parking in four inner Canberra precincts - the Parliamentary Triangle, Barton, Russell and Acton.

The scheme will raise $73 million, which will go directly into federal government consolidated revenue.

Paid parking was adopted by the government on the recommendation of the National Capital Authority, which told cultural institutions it was willing to provide financial assistance to implement the policy.

War memorial director Brendan Nelson has asked the NCA for $1 million, the estimated cost of modifying the car parks.

Defence has objected strongly to paid parking being forced on to its Russell offices, saying there was no need to keep out tourists.

The decision to introduce paid parking sparked debate about the lack of amenities for workers in the zone, compared with counterparts working close to town centres.

An inquiry by a parliamentary committee said the NCA should be directed to develop a strategy for retail services and childcare in the parliamentary zone when paid parking is introduced. It also recommended a park-and-ride facility and that the Centenary Loop shuttle bus be made permanent.

The committee accepted pay parking was a ''useful strategy'' for managing parking.