Natalie Bennett has been elected the new leader of the Green Party in England and Wales and promised to fight the coalition Government's "economically illiterate cuts".
The 46-year-old Australian-born former journalist was declared the victor of a ballot of party members - beating off the challenge of closest rival Peter Cranie in the final round of a contest fought under the STV system of proportional representation.
The vacancy arose after the party's first and only MP, Caroline Lucas, stepped aside as head of her party.
The party will announce the result of a vote for a new deputy leader later after delays to the vote counting forced a postponement. Green Party equality rules mean of the two posts, a man and a woman must be elected.
Ms Bennett will head straight into the party's autumn conference, taking place in Bristol from Friday, where she will deliver the keynote speech.
She told a press conference: "I stood because I believe in the radical vision that the Green Party has for the future of Britain. It offers, I think, the only viable way forward for British people, for the world.
"We need to not have the economically illiterate cuts we are seeing now; what we need to have is investment in the future. Investment in homes, investment in jobs, investment in energy conservation and renewable energy and public transport. There are so many things we need to be investing in now and creating jobs, not throwing people into unemployment."
The party would introduce a living wage and sufficient benefits to ensure "the chance of a good life for everyone in Britain", she said. And the economy needed to be "relocalised", returning manufacturing to the UK and supporting farmers in providing food, and the City reined in to stop it "running riot" towards another economic crash.
Ms Bennett confirmed that the party would pursue the votes of disillusioned Liberal Democrat voters "desperately looking for a home", but insisted that it was also intent on winning over many Labour supporters and "even some Tories". She said: "We can appeal to a broad spectrum. We have a message for a different kind of British future that can appeal to a broad range of people. People have gone back to voting Labour but there is not much enthusiasm for it."
Ballots closed on Friday, with party members choosing between Ms Bennett, Mr Cranie, Pippa Bartolotti and Romayne Phoenix. After the two outsiders were eliminated, the final round saw Ms Bennett triumph by 1,757 votes to 1,204. The deputy leader contenders are Will Duckworth and Richard Mallender.