The Green Party has launched its campaign for next month's English local elections, promising to be the "true opposition" to the coalition.
Leader Caroline Lucas said the Conservatives, Lib Dems and Labour had all broken promises and urged the creation of a more honest politics.
She called for more local action to improve the environment and a halt to the government's spending cuts.
The party is running 1,605 candidates for council elections on 5 May.
At the party's official campaign launch in central London, Ms Lucas said: "We have a government that is handing financial settlements to local councils which mean they are going to make horrendous decisions and big cuts.
"It's crucial that there are Green councillors to protect people from the most harsh of those cuts."
She added: "Our whole analysis of the cuts project is that it's the wrong approach. Yes, we need to address the deficit but a better way is to get people back into work to ensure there are more taxes coming in.
"Otherwise there is a greater risk of a double-dip recession. We can already see what extreme austerity is doing in countries like Portugal and Ireland."
Ms Lucas said the Greens expected to gain councillors in the party's power bases, which include Brighton and Norwich, and elsewhere across England.
She called on councils to protect the "most vulnerable" in society from the impact of budget cuts and also for local authorities to do more to promote the use of renewable energy sources.
The Greens' election broadcast will air on 27 April. It features Ms Lucas "ambushing" an audience at a west London comedy club to tell them about her party's policies and call for a less "cynical" form of politics.
She told the BBC: "It is trying to make the point, in what is usually a comical setting, that the issues we are dealing with are very serious.
"We are the true opposition party and we have the people and experience to do that job across England."
The Greens have two Members of the European Parliament and Ms Lucas became the party's first Westminster MP at last year's general election.