Mr Key today used a Dunedin campaign stop to detail how National intends to get better value for money out of the public service.
He said a "Cabinet Expenditure Control Committee" would be set up, which all departmental chief executives would have to report to after reviewing their spending "line-by-line".
"Based on the information it receives, the committee will be able to initiate in-depth spending reviews of particular areas of government administration to ensure the best value for taxpayers and users of public services."
Mr Key reiterated National's plan to cap the size of the core bureaucracy.
He also said the party would limit new spending in its first budget to priorities identified in the election campaign and priorities that could not be deferred.
"In the period immediately ahead, families and businesses will have no option but to behave with restraint and will be entitled to see similar restraint reflected in the operation of government agencies funded by their taxes," he said.
"This is a time in which the public sector must play its part by seeking to improve productivity and the delivery of core services to the public."
Mr Key indicated government communications staff could be the first to feel the axe.
He said the numbers of such staff had swelled from 238 six years ago to 505 in July this year.
"New Zealanders know the service provided by these departments isn't twice as good."
