Opposition employment spokesman Brendan O'Connor will commit his party on Thursday to dumping the controversial Abbott-era public sector bargaining policy which has led to two years of industrial strife in the public service and other government workplaces.

Labor insiders say the party hopes the move will boost its chances in several marginal seats with large numbers of public service or military-employed voters, including the bellwether Eden-Monaro outside Canberra.

Instead of the Coalition government's hard line on pay and conditions for government employees, public sector workers will not be forced to give up swathes of conditions and entitlements under Labor's policy.

There also will be a "just" pay outcome, Mr O'Connor says, although Labor gave no indication of what sort of offers might be on the table should Labor win office on July 2.

More than 80 per cent of the 150,000-strong public service are still resisting the sweeping changes to their workplace arrangements mandated by the policy developed by then Employment Minister Eric Abetz soon after the Coalition's 2013 electoral victory.

Thursday's announcement was the moment senior Canberra bureaucrats were dreading, knowing they face an even more difficult time trying to settle their longstanding workplace disputes before the election.

It is also understood that pressure was mounting on Mr O'Connor from unions and his party colleagues to announce a policy before a massive workplace ballot of 20,000 Defence Department public servants on April 28.

Labor will also be hoping to garner support within the Australian Defence Force community where resentment lingers about the treatment of sailors, soldiers and Air Force personnel under the Coalition's policy.

The Abbot government walked into a political storm in late 2014 when it tried to force a workplace deal based on its bargaining on the Defence Force and was forced to back down first on conditions and then on pay.

Other seats with large numbers of public-sector voters and where Labor's policy looks set to feature heavily in its campaign will be the Townsville-based seat of Herbert, Gilmore on the NSW south coast and Solomon in the Northern Territory.

The centrepiece of the Coalition policy is the removal of workplace rights and conditions from legally enforceable enterprise agreements and recasting them as "policy" with agreements written under the policy also cracking down heavily on the ability of unions to operate in public sector workplaces.

Mr O'Connor told Fairfax the policy was "unfair, ideological and has resulted in a complete mess".

"Mr Turnbull is blackmailing workers," the Labor frontbencher said.

"The Turnbull ultimatum? You don't get a pay rise unless you sacrifice conditions of employment.

"Workers, unions and public service agencies know there is a pathway to resolution but that it is only Labor that can negotiate that pathway.

"A Shorten Labor government will remove the Abbott-Turnbull government requirement that forces agencies to strip rights and we will provide a fair-pay outcome that will ensure workers do not go backwards in real terms, unlike the Abbott-Turnbull government.

"Labor will have an approach to enterprise bargaining that actually improves the capability of staff and provides fairness in the workplace."