"When you cheat on your partner you add to the heartbreak, pain and jealousy in the atmosphere," their spiel went. "CheatNeutral offsets your cheating by funding someone else to be faithful and not cheat. This neutralises the pain and unhappy emotion and leaves you with a clear conscience."

The parallel with carbon offsetting is obvious.

A policy that allows Australia's biggest polluters to keep polluting - indefinitely - so long as they buy offsets doesn't deal with the pain caused by their ongoing climate-heating emissions, does it?

Unfortunately, the ability for companies to purchase unlimited carbon credits to meet their emissions reduction targets is a feature of the proposed design of the safeguard mechanism - the Albanese government's main policy to tackle climate emissions from big industry.

Firstly, the government's proposed design for the safeguard mechanism is a big improvement on the previous government's design. Secondly, while it has been improved in several ways, there remain some very big flaws that need to be fixed before it passes the parliament.

Under the Abbott-Turnbull-Morrison design the safeguard mechanism allowed big emitters to increase their emissions without penalty and calculate new, laxer pollution baselines.

While some of the rules around the safeguard have been tightened up in the Albanese government's version, the unlimited offsets provision remains.

It would allow companies like Woodside, Glencore and Santos - which have done more than enough climate damage already and are making massive profits - to pay to keep polluting.

Australia and Kazakhstan are the only countries in the world that plan to allow big polluters access to 100 per cent unlimited offsets.

It's no exaggeration to say the unlimited offsets loophole puts at risk Australia's net zero by 2050 target.

The provision also threatens our national 43 per cent by 2030 target - which was meant to be a floor, not a ceiling.

And what that means is more pain for Australian communities: more flooding, more heatwaves and more bushfires, thanks to the 'cheat offsetting' of the big polluters.

The unlimited offsets provision would weaken the safeguard mechanism's capacity to drive real emissions reductions through changes to our electricity system and industrial processes.

The Greens are right to say that to have a safe climate we must stop approving new coal and gas projects. And Labor is right to say we need to end the climate wars and get moving on climate policy. We must do both.

Burning coal and gas is the number one cause of global heating. The world's climate scientists and bodies like the International Energy Agency have been saying this for years. And Australia is a big contributor - especially via the coal and gas we dig up and export. They may get burnt in another country, but they are damaging the Great Barrier Reef, the Wet Tropics and the Australian Alps.

So, the government has to stop approving new coal and gas. How could it achieve this?

It could be done via the safeguard mechanism, but perhaps it's not the best tool It's a system set up to regulate the biggest emitters within Australia and doesn't cover coal and gas that is exported.

It could be done by mandating the assessment, avoidance and mitigation of climate pollution in the Environment Protection and Biodiversity Conservation Act.

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Bizarrely, Australia's national environment law ignores climate pollution from proposals like new coal and gas mines even though climate change poses a grave risk to nature. This could be mandated immediately, through regulations.

Whatever policy instrument is used, the Albanese government needs to find a way to stop approving new coal and gas projects. And it needs to get unlimited offsets out of the safeguard mechanism.

Recent analysis by Climate Analytics highlighted the fundamental scientific shortcomings of land sector offsets, such as tree planting and forest regeneration, which account for more than half the total offsets generated to date.

Climate Analytics' research shows carbon emitted from the fossil fuel industry stays in the atmosphere for hundreds, even thousands, of years - much longer than the land-based offset, which in Australia is guaranteed for 25 to 100 years at best.

Offsets should only be used as an absolute last resort. They should only be accessed once a company can prove it is making genuine efforts to cut emissions, with access to offsets reducing over time. They should not be available for coal and gas companies which are simply not part of a clean, safe climate world.

It's time to stop cheating on future generations.