If the UK's biggest banks and investors were a country, they'd rank 9th in the world for the carbon emissions they're responsible for.
That's the striking conclusion of a new analysis by Greenpeace and WWF.
The study assessed the emissions associated with the global investments of 15 British banks and 10 asset managers.
A spokesman for UK financial institutions said they were committed to being net zero by 2050.
Net zero refers to the reduction of carbon emissions as much as possible, so that any remaining emissions are balanced out by absorbing an equivalent amount from the atmosphere - through planting trees, for example.
The research, led by South Pole, a specialist environmental analysis company, is an attempt at a rough estimate of the carbon footprint of the choices made by the giants of the British financial world.
Using data from 2019, it finds that they were responsible for a total of 805 million tonnes of greenhouse gases.
That's 1.8 times more than the UK as a whole emitted that year and slightly more than Germany.
According to Greenpeace, this shows that the financial sector should be considered "high carbon" along with the oil and gas industry, coal mining, aviation and transport.
The estimates do not include emissions associated with insurance underwriting or property so the real figure may be far higher.
The executive director of Greenpeace UK, John Sauven, described finance as the "UK's dirty little secret".
"Banks and investors are responsible for more emissions than most nations and the UK government is giving them a free pass," he said.
"How can we say we're 'leading the world on climate action' while allowing financial institutions to plough billions into fossil fuel production every year? The claim is almost laughable."
The chief executive of WWF UK, Tanya Steele, called on the financial sector to have zero carbon transition plans that cover their investments all over the world.
"Trying to set a path to net-zero emissions without tackling the UK financial sector is like sticking a plaster when the patient needs open heart surgery," she said.
"Despite seeing ambitious commitments to tackle the climate emergency, our finance sector is still driving global investment towards the old, destructive ways of doing business that are destroying our one shared home."
In response, a spokesman for UK Finance, representing the banking and finance industry, did not challenge the findings of the new analysis.
He said lenders are "playing a leading role in the shift to net zero finance".
"Last month the UK's six largest banking groups were among the founding members of the UN's new Net Zero Banking Alliance, committing to net-zero emissions from their portfolios by 2050 or sooner," he added.
"The industry will continue work with others to help mobilise capital in a way that takes account of local community and environmental needs."
Ahead of the COP26 climate summit, due to be held in Glasgow later this year, every sector of the economy is set to come under greater scrutiny and to have its green credentials challenged.
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