The UK Government’s announcement last week that it is going to leave the climate-wrecking Energy Charter Treaty is a huge win for all of us who have been campaigning hard for this to happen. More importantly though, it’s a big win for the climate.

The treaty may be something that most of us have never heard of but it’s also the most significant single international treaty threatening the transition to a zero-carbon economy. And, until today, that threat was as real here in Scotland as anywhere else.

At the core of the ECT is a mechanism which allows foreign companies to sue governments outside of the national legal system in secretive tribunals for policy decisions that they believe will threaten their profits.

Fossil fuel companies can and have been using it to sue governments for decisions they’ve taken to do things such as stopping offshore oil drilling to protect fragile marine areas and the climate, or committing to ending the burning of coal because of its climate-wrecking emissions.

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The amounts at stake can be in the billions and the ECT has to date generated at least 135 claims, making it the world’s most litigated investment agreement.

Being in the treaty meant that some of the bold but very necessary action on climate change that the Scottish Government needs to take was being put at risk.

For example, the Scottish Government’s draft energy strategy and just transition plan suggests it may oppose new onshore oil, gas and coal and adopt a presumption against new oil and gas exploration in the North Sea.

From the point of view of the climate emergency, there is an urgent need for these things to happen but the Government could have been challenged by fossil fuel companies under the ECT which would allow them to sue for loss of future profits.

That’s a huge threat to vital and necessary action on climate change.

The National: Liz Murray says the treaty threatened Scotland's transition to a zero-carbon economyLiz Murray says the treaty threatened Scotland's transition to a zero-carbon economy

Leaving the treaty takes away a scandalously powerful and undemocratic tool that fossil fuel companies have had at their disposal for decades and tips the balance of power away from them and back towards governments.

What Scotland and other countries need is policy space to be able to experiment with ideas and get the climate transition right. The ECT was a straitjacket which has now been removed.

Of course, the fossil fuel industry is still incredibly powerful and benefits from subsidies, tax breaks, incredible levels of access to government and access to international climate talks.

And companies’ profits have been hitting new highs, so their efforts to protect themselves are unlikely to recede without further government intervention.

The Scottish Government needs to push back wherever it can. It doesn’t need to do this alone though – and actually such a mammoth task as switching away from fossil fuels and embracing the clean alternatives is probably better done by countries planning and working together.

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We’re not talking about ending coal, oil and gas tomorrow but it’s clear it’s now the end game for all those polluting fuels. There needs to be a global plan to move the world out of the fossil fuel era, with international co-operation to ensure that workers, communities and indeed whole countries don’t get left behind.

We must fight for measures such as persuading the Scottish Government to back calls for a Fossil Fuel Non-Proliferation Treaty.

Different in just about every way to the Energy Charter Treaty, it would set a global framework for a fast, fair and financed transition away from fossil fuels and give governments a collective mandate to take the action they so urgently need to take.

Already momentum is growing around the world, with more and more places from Colombia to California backing the call.

Given the Scottish Government’s climate progress in other areas – such as loss and damage – it only makes sense that we are next.

If the balance of power is to truly tip away from the fossil fuel giants, ambitious calls to action like these are something the Scottish Government should throw its weight wholeheartedly behind, now that we are free from the iron grip of the Energy Charter Treaty.

Liz Murray is head of Scottish campaigns at Global Justice Now