The advisors to key Coalition government MPs and Senators may soon have to embarrass their bosses.

The Government continues its struggle to sign the public sector up to new pay deals, with staff at the Administrative Appeals Tribunal, National Museum and Department of Agriculture voting to reject proposed enterprise agreements this week.

Rebel Coalition staffers have reportedly told their colleagues that the harsh bargaining “fails the Coalition ethos” of reward for hard work.

But Josh Manuatu, the bargaining representative for Coalition staffers and an advisor to Senator Eric Abetz, labelled the rebels as “gutless and unconvincing”. 

Greens and Labor staffers will vote no, and if those attached to Coalition and Nationals figures do not come around, another agreement will be voted down.

Insiders have told reporters that they feel undue pressure to toe the party line.

Meanwhile, the Agriculture Department has rejected its pay deal for an unprecedented fourth time.

Staff were offered a 2 per cent per year pay rise - the maximum being offered across the public service - and a promise there would be “no loss of conditions” though they would have 30 minutes added to their working day.

But the deal offers no back pay and maintains the same increment system for staffers, which many regard as outdated and unfair.

Mr Manuatu said opposition to the deal was actually low, despite them being rejected by now tens of thousands of public servants.

“Most people find this kind of gutless behaviour from unnamed email accounts and unnamed sources in the media unconvincing and disappointing,” he told Fairfax.

“The simple reality is that this is a fair, reasonable and responsible deal – 2 per cent per year most likely before Christmas.

“The Coalition Bargaining Representatives are advocating to our colleagues to support the offer and the feedback has been positive.”