SNP Westminster leader Stephen Flynn has written to the Prime Minister urging him to rethink a reported U-turn on the UK Government's net-zero promises.

Rishi Sunak is poised to announce the watering down of climate change commitments despite a backlash from industry and the prospect of a damaging rift in the Tory party

The Prime Minister will deliver a speech in Downing Street on Wednesday afternoon setting out a “proportionate” approach to cutting emissions.

Measures being considered include weakening the plan to phase out gas boilers from 2035 and delaying the ban on the sale of new petrol and diesel cars – currently due in 2030 – by five years, the BBC reported.

READ MORE: Rishi Sunak abandons promise to daughters on climate change

The National: Rishi Sunak faces a tough parliamentary year as most voters tell think tank More in Common they want a change of government (Dan Kitwood/PA)

The potential policy shift also alarmed the car industry, which has invested on the basis of a 2030 shift away from petrol and diesel.

It comes weeks after no new offshore wind farms were commissioned in a key UK Government auction.

Below is Flynn's letter to Sunak in full, in which he accuses the Tory chief of having "thrown in the towel" and "sabotaging" Scotland's energy future.

Dear Prime Minister,

There is a global race to a net-zero future, and you've just thrown in the towel.

Your clear intention to renege on the promises made to citizens and businesses on achieving green growth and green jobs, puts at risk both our climate obligations and our economic future.

Your predecessors in office were very successful in making a mess of the present - you seem intent on making a mess of all our futures.

This disgraceful decision will hit hardest in Scotland. We have the energy, the people and the ambition to compete in that global race to net zero - an ambition which will help deliver economic growth, cut energy bills, cut emissions and create jobs. More than ever, Westminster control is now holding back that massive potential.

For many in Scotland, this will inevitably feel like history repeating itself. Westminster stole Scotland's energy past, now it wants to sabotage our energy future.

All the evidence tells us that we can protect and create jobs in Scotland by ensuring that we get the energy transition right, but your Westminster government now doesn't even seem to want to have a transition, just a cliff edge.

The clearest outcome from your intention to drop out of the global race to net-zero is that both the US and the EU will easily beat the UK in this green gold rush. With both the Inflation Reduction Act and the European Green Deal, they know where the economic growth of the future will come from, and they are heavily investing in it. They will secure the jobs, the technology, the energy security, and the economic growth that will flow from quickly transitioning to green energy.

Backwards Britain will be left behind.

During my time at Westminster, I have often repeated the phrase that "Scotland has the energy, it just needs the powers". That feels very true today. Your decision shows the catastrophic consequences of that reality.

I feel obligated to urge you to reconsider your decision but, in reality, I know you won't. However, for people in Scotland, this damaging decision is yet one more reason to reconsider the damaging consequences of remaining under Westminster control.

It's time that Scotland had the power to choose a different path with the powers of independence.

Yours sincerely,

Stephen Flynn