The Albanese government is facing a growing employer revolt over its bill for pay deals covering multiple businesses, after consultations confirmed the reform will not be limited to low-paid workers.

On Thursday the employment department revealed details of the industrial relations bill in confidential consultations with peak union and employer bodies.

The bill, to be introduced in the budget sitting of parliament next week, enacts several election commitments to improve gender pay equity and multi-employer bargaining, a union proposal Labor signed up to at its September jobs and skills summit.

Since the summit, employer groups had sought to limit the reform to tweaks of the existing system that allows workers in low-paid industries to apply to bargain together.

Several sources who either attended the meeting or were briefed on the bill’s content said the multi-employer bargaining reform was broad, indicating employers had lost the bid to limit the change and prevent workers going on strike in support of pay deals covering multiple businesses.

One described it as a “very material” change, while another said it is understood to allow any workers with a “common interest” to bargain together, suggesting both employees in the same occupation or the same supply chain could band together.

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Earlier on Thursday, the chief executive of the Business Council of Australia, Jennifer Westacott, said business was “concerned” by the reform.

Westacott told Sky News the economy grows “through innovation” which is best fostered by pay deals “at an enterprise level”.

“We are concerned about some of the demands from some of the unions, that they want to see widespread strike action that will freeze-dry the economy.

“What we want to see is a simple system, it’s easier to bargain, people are encouraged to bargain, and they bargain in good faith.”

Employer groups are considering going public with their concerns as early as Friday, to prevent a lack of scrutiny on the bill in budget week.

Employers believe they have convinced the government to put sensible qualifications on other Labor commitments, including an exemption for high-income earners to the proposed ban on rolling fixed-term contracts and preserving an avenue to terminate pay deals for commercial viability.

And while the Albanese government will have a fight on its hands with employers over the bill, it is also facing pressure from its union base over a lack of action to combat sky-rocketing gas prices.

On Thursday the Australian Workers Union national secretary, Daniel Walton, wrote to Anthony Albanese and all federal Labor MPs to warn that the new heads of agreement with gas companies will not keep prices down.

“I believe if the current position on gas policy is maintained, thousands of Australian manufacturing jobs will be lost during this term of the Albanese government,” he said.

The AWU is calling for the Australian Competition and Consumer Commission to gain power to set a gas price cap and enforce what is currently a voluntary code of conduct to reign in cartel conduct by the gas industry.

Labor’s proposals to review the domestic gas security mechanism and possibly shorten the time to reserve gas don’t go far enough, according to the AWU, which wants a price trigger to “ensure that runaway gas prices directly trigger the redirection of gas from exports to domestic users”.

Walton said “the measures attempted to date are having no meaningful effect”.

“In fact, one manufacturer told us this week their contract quotes have actually rocketed up since the heads of agreement came into force.”

The Albanese government also faces a fight to win the Senate votes for its industrial relations bill, which it hopes to pass this year.

The independent senator David Pocock has set his price by linking his vote on the bill to wiping the Australian Capital Territory’s public housing debt, at a cost of $100m.

Asked if he is looking to horse-trade his vote, Pocock told Radio National: “Yeah, housing is something that is important across the country, here in Canberra we’re at the forefront.”

“These IR reforms are about getting real wage growth for frontline workers … and housing is a huge part of that, so I see them as connected.

“Whether or not this is tied to my support for IR, I haven’t seen any details of the IR reform yet.”

Pocock told Guardian Australia the clearest consensus from the jobs and skills summit was that “real wage growth is a priority”.