The public service union wants a solution to the car parking crisis in Canberra's Parliamentary Triangle.
The CPSU says that car parks in the precinct are being closed without any consultation with the thousands of public servants who work there.
The union's deputy national president, Alistair Waters, says that Commonwealth workers are slowly being squeezed by successive closures.
He will present a petition on Wednesday to the federal member for Canberra, Gai Brodtmann, signed by more than 2000 public servants based in the triangle calling for more transparency when car park closures are being planned.
''We started doing this petition when the National Capital Authority started making changes to parking without consultation,'' Mr Waters said.
''There's an inter-governmental committee which the National Capital Authority chairs with ACT government, but every time we talk to the ACT government about it, they're very keen to point out that it's the NCA that runs the Parliamentary Triangle. We think some decisions need to involve some actions from the ACT as well.''
He said the lack of parking in the national precinct was exacerbated by its lack of retail infrastructure, leaving public servants reliant on their cars for every routine trip.
''No one is asking for a big supermarket, but we don't even have things like a Post Office or a dry cleaner and parking is just getting worse and worse,'' he said.
''We really want to know what the NCA is up to and what they're thinking about.
''We think that any solution needs to involve looking at the parking and public transport for the area and looking at the facilities that are available in the area, so there's less requirement for people to have to make trips at lunchtime or during the day.''
The union says it gathered the signatures in an ''old-school'' way with campaigners approaching local workers as they parked their car in the morning.
''With the limited public transport options available, is it any wonder so many people rely on a car?
''However, the Authority is making finding a car park even harder with recent decisions to close car parks, such as the one on the Patrick White lawns [at the National Library] made without consultation.
''The petition calls on the Minister for Regional Australia, Regional Development and Local Government to direct the Authority to consult with stakeholders on the implementation plan for parking and public transport in the Parliamentary Zone, developed by the Intergovernmental Committee on Parking, which the Authority chairs.''