Activists from the Extinction Rebellion drape a banner across Marble Arch as part of a protest in central London, Britain, April 16, 2022. REUTERS/Henry Nicholls/File Photo

Britain unveiled a new taskforce on Monday to write rules forcing financial firms and listed companies to publish plans from next year for transitioning to a net zero economy by 2050.

Last November at the COP26 UN Climate Summit, British finance minister Rishi Sunak said companies would have to publish a plan from 2023 with targets to mitigate climate risk, interim goals between now and 2050 and measures to meet them.

It is part of Britain's commitment to make the UK the world's first net-zero aligned financial centre.

The taskforce will develop "rigorous and robust" measures to tackle greenwashing - inflated green credentials - and support companies to establish "investable and accountable" transition plans, the finance ministry said in a statement on Monday.

"Preventing the worst impacts of climate change will take all businesses developing ambitious, consistent transition plans to get us to a low carbon future," said Amanda Blanc, CEO of insurer Aviva and co-chair of the new Transition Plan Taskforce.

It has a two-year mandate to set up good practices for transition plans, along with a 'sandbox' to test the new plans.