Unions: We've been locked out of the budget lock-up

UNIONS have hit out at the Abbott Government's budget process, claiming they have been "locked out" of the annual budget lock-up today.

Three top unions, the Community and Public Service Union, AMWU and Australian Services Union have complained they have been prevented entry to the budget preview.

Each year, the government allows media and interest groups several hours to read budget documents before releasing them publicly, but this year unions have claim they were left out.

While five three representatives from the Australian Council of Trade Unions will be let in, the public service union, AMWU and ASU say they were blocked.

A statement from the three unions said all their members were likely to be impacted by the budget, claiming the government was "trying to escape any accountability for their budget".

Feeding fears of expected cuts to pensions, health and a host of other areas of government spending, the statement said the budget "must be a document that seeks to attack the rights of working Australians.

"Just like the Commission of Audit, this confirms the government isn't interested in the views of anyone but big business," the statement reads.

"What we want to know is - how many people will be there representing industry groups? How many people will be there representing business?"

Questions put to the Treasury, which runs the budget process in Canberra, have remained unanswered.