The prime minister, Anthony Albanese, has confirmed next month’s federal budget will not include a new tax on existing gas export contracts as he criticised the “populist” campaign calling for a levy on producers.

As reported last week, Albanese was poised to reject pressure to introduce a 25% tax on gas exports amid concerns the intervention could alienate the same Asian trading partners Australia is relying on for supplies of diesel and petrol.

In a speech to the Chamber of Minerals and Energy of Western Australia on Wednesday, the prime minister directly tied gas exports to Australia’s fuel security amid the global energy crisis.

“And the middle of a global fuel crisis is the worst possible time to jeopardise these partnerships, or the investment that underpins them,” he said.

“This is why I can confirm that the budget will not undermine existing contracts on gas exports.”

Advocates for a 25% export tax want the new levy to replace the petroleum resource rent tax (PPRT), which they argue is broken and failing to extract enough revenue from the gas giants.

In a Q&A after the speech, Albanese defended the existing PRRT, which Labor tweaked in 2023.

“The changes are designed to lift up the amount of revenue over a period of time, which makes sense, because you have an upfront investment of tens of billions of dollars, and so therefore the design is a sensible one that makes sense,” he said.

“Without that investment, it’s not just about international [exports]. There’s a lot of focus on exports. Without that investment you wouldn’t have a domestic gas reservation here in WA because you wouldn’t have the gas. And that’s a pretty important point that is lost in some of the populist rhetoric, whether it be the sort of coalition of the far left or the far right.”

More details to follow