Maverick Democratic Senator Joe Manchin on Wednesday agreed to support a new bill with $369bn for carbon reduction and energy investment, unexpectedly breathing new life into President Joe Biden’s faltering US climate agenda.

The $433bn agreement negotiated between majority leader Charles Schumer and Manchin would represent the most ambitious action ever taken by Congress to address climate change, although the measure they are calling the Inflation Reduction Act of 2022 will require support from every Democrat to pass the evenly divided 100-seat Senate.