Tony Abbott has fired a significant broadside ahead of the resumption of federal parliament next week, declaring the party room has not agreed to the national energy guarantee, and should not be forced to “rubber stamp Labor’s policy”.

As the energy minister, Josh Frydenberg, attempts to coax his reluctant state counterparts into a deal on the policy, Abbott has thrown down the gauntlet, declaring the Neg “bad policy” and the economic modelling underpinning it “fanciful”.

The former prime minister used a regular interview on 2GB to brand “not true” Malcolm Turnbull’s repeated insistence the Coalition party room had already given the policy the green light, effectively rendering next Tuesday’s party room discussion a formality. “We haven’t agreed,” Abbott said.

Upping the brinkmanship, Abbott also cut across Turnbull’s argument that the Neg would lower power prices. He declared the policy “won’t bring prices down”.

Abbott’s escalation follows a Victorian government suggestion that Frydenberg delay a final state sign-off on the Neg until after parliament has legislated the scheme’s emissions target.

Guardian Australia understands the Victorian energy minister, Lily D’Ambrosio, put her case to Frydenberg after the state’s cabinet resolved to toughen its negotiating stance on the Neg and pursue a list of changes to the scheme that could torpedo the policy.

Separately to the Victorian pitch to defer the crunch point, the ACT’s climate minister, Shane Rattenbury, has also put forward a suggestion in an attempt to break the current deadlock, proposing an earlier review of the 26% emissions reduction target than 2024.

Rattenbury wrote to Frydenberg on Tuesday proposing that the target be reviewed no later than 2024, “and that the final design of the Neg includes a mechanism to initiate a review immediately should electricity sector emissions reach a 24% reduction on 2005 levels”.

It is possible the Commonwealth could give ground on the timing of the review, but the government is holding firm on legislating the target as opposed to implementing it via regulation – a pathway that would make it easier for a future government to scale up.

Officials say Victoria told Frydenberg that reaching a final resolution of the emissions reduction target in the federal parliament could help clear some of the roadblocks making it difficult for the states to sign up to the policy.

The Turnbull government wants the target to be 26% but Labor federally has signalled it wants to increase the level of ambition in the event the legislation makes it through the Coalition party room next week, and into the parliament for consideration.

While the states will need to pass legislation to establish the Neg – which is why the current negotiation is playing out through the Coag energy council – the policy doesn’t activate until a federal emissions reduction target is settled, and doesn’t take effect until 2020.

All the Labor states are also concerned that an early sign-on could allow the Commonwealth to bolt on extras, such as government support for coal-fired power plants, that would intensify the backlash the states are currently facing from the progressive activist group GetUp and from sections of the environment movement.

The Andrews government is firmly in the sights of progressive groups campaigning against the Neg and the state goes to the polls in November.

Victoria has set four concrete conditions it says it wants met, which, if insisted upon, could torpedo the Neg.

It says emissions reduction targets can be only allowed to increase over time “and never go backwards”; future targets will need to be set by regulation; the targets will need to be set every three years, three years in advance; and it wants the emissions registry to be fully transparent.

The Turnbull government – which faces internal pressures on the policy – is increasingly frustrated with the Labor states digging in their heels in the lead-up to the Coag energy council meetings starting on Friday. The government is insisting the emissions reduction target is a matter for the commonwealth, not for the states.

The prime minister said on Wednesday: “Daniel Andrews has got to decide whether he wants Victorians to pay more for electricity, or less”.

“What Daniel Andrews has got to do is stop being pushed around by the Greens, who basically want to de-industrialise Australia, what he’s got to do is stand up for Victoria, a big manufacturing state that needs affordable power, stand up for Victorian families, sign up to the Neg and we know that will deliver the certainty that enables industry to invest.”

Frydenberg also declared Victoria needed to get on with it. He said the states needed to leave the setting of the target to the Commonwealth, and let the political debate play out in the federal parliament, not through the Coag energy council.

He said the debate over ambition in the target can “play out in federal parliament”.

“These are not issues that are within the remit of the state governments. What is within the remit of the state governments is the design of the guarantee, as the energy security board has put forward”.