The bill would "require the Secretary of State to achieve climate and nature targets for the UK; to give the Secretary of State a duty to implement a strategy to achieve those targets; to establish a climate and nature assembly to advise the Secretary of State in creating that strategy; [and] to give duties to the Committee on Climate Change and the Joint Nature Conservation Committee regarding the strategy and targets.

It highlights how much our politicians are defying the urgency of the moment and—by presenting clear and precise proposals to drastically reduce carbon emissions and restore biodiversity in the same typefaces and official vocabulary as the laws that define whole swathes of our lives—it makes the prospect of radical action eminently imaginable.

[6]Former Cabinet Minister for Energy and net zero tsar, Chris Skidmore, wrote in Labour List that:It’s time for a new generation to carry us forward.

[9] 2021-22 session In the 2021-22 session, Caroline Lucas tabled the bill on 21 June 2021 with the support of 11 co-sponsors—Alan Brown (SNP), Ed Davey (Liberal Democrat), Stephen Farry (Alliance), Barry Gardiner (Labour), Claire Hanna (Social Democratic and Labour Party), Ben Lake (Plaid Cymru), Clive Lewis (Labour), Brendan O'Hara (SNP), Sarah Olney (Liberal Democrat), Liz Saville Roberts (Plaid Cymru) and Alex Sobel (Labour/Co-op).

The amended bill—the Ecology Bill—passed through its remaining Lords stages successfully, and was 'handed over' to Wera Hobhouse (Lib Dem) on 25 April 2023.

The amendment was supported by MPs from across the House, including Caroline Lucas, Daisy Cooper, Liz Saville Roberts, Stephen Farry, Colum Eastwood and George Howarth.

In the new 2024-29 Parliament, the Lib Dem MP for South Cotswolds, Roz Savage, tabled the bill on 16 October 2024.

Zero Hour is a c. 70,000 person-strong non-profit grassroots campaign working to build support for the bill by persuading MPs, peers, mayors, councillors, local authorities, electoral candidates and political parties—as well as businesses, unions, community groups, NGOs, charities and cooperatives—to endorse the proposed legislation.

The bill is also supported by a wide variety of environmental groups, including WWT, CPRE, AquaTerra, Faith for the Climate, Greenpeace, Friends of the Earth and Extinction Rebellion.

MPs from Labour and Labour/Co-op, the SNP, and the DUP (Jim Shannon MP, via an Early Day Motion in September 2020) are also listed as bill supporters—alongside the Scottish Green MSPs and several Plaid Cymru MSs.

Roger Gale and Simon Hoare are currently the only Conservative MPs backing the CAN Bill; however, Mark Garnier, the MP for Wyre Forest, has met local supporters to discuss the bill; as have many other Conservative MPs, peers and councillors; including Cllr John Hart (chair of Devon County Council).

UK regions On 2 December 2021, the London Assembly passed a cross-party motion to back the bill—proposed by Zack Polanski AM (Green) and Leonie Cooper AM (Labour/Co-op).