Data released this week showed the Abbott government had already shed most of the 16,500 jobs it said it would target, more than two years ahead of schedule.

Employment Minister Eric Abetz said that, given the government had delivered on its promise early, he would now review the tight restrictions he had placed on public service recruitment.

Shadow workplace relations minister Brendan O'Connor said the Coalition had showed contempt for public sector workers.

"Eric Abetz and [prime minister] Tony Abbott lied about the number of public service jobs to go, and the way in which those jobs would be lost," he said on Wednesday.

"Labor believes in an affordable, sustainable and productive public service, but crudely retrenching staff, cutting jobs, and reducing wages and conditions does not lead to a more effective workforce."

The Community and Public Sector Union's national secretary, Nadine Flood, also said the policy's early "success" was no reason to celebrate.

"The loss of almost 11,000 jobs in a year is massive for any industry," she said.

"Under this government, almost 7000 public servants have been made redundant in a year, with agencies like the Tax Office and indigenous programs in Prime Minister and Cabinet bearing the brunt."

The bureaucracy shrank by almost 11,000 staff in 2014 – the largest annual cut in more than 15 years.

The Australian Taxation Office was among the agencies hardest hit. It lost about one in six of its workforce – more than 3600 employees – which was the largest number of staff from any workplace.

Ms Flood said the government had gutted the ATO at a time "ordinary families were being asked to pay their fair share of tax while big business and wealthy individuals get off scot-free".

"We criticised Labor for cutting the public service but these cuts are almost triple the size of the largest cut under Labor," she said.

"Instead of recognising the pressure that public servants are under, all this government can do is pile it on by cutting more jobs.

"If this government is to have any credibility on the public service, then it should recognise the increased demand on services and restore funding for public services in the forthcoming budget."

The Coalition said before the 2013 election it would cut only 12,000 jobs via a recruitment freeze – allowing public servants to leave without replacing them.

However, it dropped that policy shortly after winning office, saying it had discovered what it called "Labor's secret, unfunded cuts" – efficiency measures that would require the loss of 14,500 full-time-equivalent jobs – and later replaced it with a plan to remove 16,500 full-time jobs from the Australian Public Service by June 2017.

Senator Abetz said on Tuesday that Labor and the union "should congratulate the government for managing Labor's secret cuts in an orderly and responsible way".