The Green Party will launch its manifesto today calling for a "peaceful political revolution" to end austerity and tackle climate change.
The declaration sets out what the party calls "a bold ambitious plan for a fairer society and safer planet".
As well as the environmentalist party's long-standing concerns over the ecology and global warming, it sets out plans to halt the Government's austerity programme, reverse "creeping privatisation" in the NHS and create one million public sector jobs paying the living wage.
The Greens are enjoying a surge in popularity, with membership soaring to almost 60,000 in England and Wales and the party challenging Liberal Democrats for fourth place in some national polls.
It hopes to retain its single parliamentary seat in Brighton Pavilion and to snatch others in strongholds like Norwich and Bristol.
The manifesto, entitled For The Common Good, describes climate change as "the greatest challenge of our time", insisting that only Greens are "determined to tackle it by taking serious action to limit our emissions at home and fighting for a fair global deal that secures humanity's shared future".
It argues that action on climate change will "create jobs, reduce energy bills and make life better for ordinary people".
The party also promised "a fair economy that works for all" and said it would "end austerity and restore the public sector, creating over one million good jobs that pay the living wage".
Launching the manifesto in east London, Green leader Natalie Bennett is expected to say: "Austerity has failed and we need a peaceful political revolution to get rid of it.
She will describe the party as an alternative to "tired, business-as-usual politics."