Malcolm Turnbull has talked down the hip-pocket saving from his new gas policy, saying it's aimed at temporarily shoring up vital supplies for business and industry.
From July 1, the government will be able to put in place export controls when there is a shortage of gas in the domestic market.
Australia is set to become the world's largest exporter of liquefied natural gas by 2020 but there have been warnings of shortages in domestic supplies for households and businesses.
Under the new regulations, if an exporter draws more from the domestic market than they put in they will need to show how they will fill the shortfall as part of their overall production and exports.
The government will not prescribe how the gas exporters fill the shortfall.
The prime minister said on Thursday that domestic gas prices were sometimes four or five times more than those on offer in the US.
"People are being offered prices of $20 a gigajoule (in Australia). It should be around half of that, or less," Mr Turnbull told ABC radio.
Labor leader Bill Shorten questioned whether the prime minister was falsely promising to halve gas prices for households.
"Without the gas companies confirming that, what Mr Turnbull is saying is just hot air," he told reporters outside Melbourne.
Mr Turnbull later clarified he was talking about wholesale prices and the main benefits would flow to businesses that relied heavily on gas.
"If you're a household, a family, the wholesale price of gas is between 15 and 20 per cent of the cost on your gas bill because the gas company obviously has to get the gas to you," he told reporters in Brisbane.
"What we have been focusing on is the wholesale price of gas because that is fundamentally ... life and death, the absolute, essential, staple commodity for so many industrial businesses."
Mr Turnbull said the long-term solution was to develop more gas, which was being blocked by states such as Victoria, which imposed bans on onshore gas exploration and development.
He said the short-term measure would protect 65,000 jobs in gas-dependent industries and bring Australian gas prices in line with the global market.
Manufacturing Australia executive director Ben Eade, who met Mr Turnbull on Thursday, said the intervention was welcome, but more needed to be done to boost supply and push down gas prices.
"This isn't an energy problem, it's a jobs problem," Mr Eade said.
"Manufacturing is especially threatened, but the fact is entire supply chains are at risk, from agriculture to food, infrastructure and housing."
Greens energy spokesman Adam Bandt said the government was making fanciful and reckless promises.
"We need the cheap, clean and plentiful energy that renewables can offer and we need the prime minister to develop a plan that makes this a priority," Mr Bandt said.
Gas producer Santos will seek clarification of how the new policy will work in practice.
"Santos will work collaboratively with government and its joint-venture partners to ensure an outcome in the best interests of its shareholders," it said in a statement.