Big Issue founder John Bird has decided he will no longer stand as a candidate to be mayor of London, and will devote his time to fighting poverty instead.
John Bird launched the Big Issue in 1991 for homeless people to sell
He said he planned to launch a political "movement" next year.
"We're going to try and do what the CND did over the bomb, but over social injustice," he told the BBC.
"We need parties to stop spending money on maintaining people in poverty," he added, calling for "some real grown-up thinking" on the matter.
When Mr Bird launched his mayoral manifesto in May, he promised to enter into a partnership with Londoners, working together with them to improve their city.
He said he would issue anti-social behaviour orders (Asbos) to businesses which wrecked the lives of Londoners, such as supermarkets which disturbed residents with early-morning deliveries.
He also promised to hold a referendum to decide whether to continue with the congestion charge.
Now he no longer wished to try to replace Ken Livingstone as mayor in elections next May, he told BBC News 24's Straight Talk programme.
'Not an apologist'
"Why do I want to manage a decline? Why do I want to manage a crisis?
"I'd have to do the Ken Livingstone thing - go out there and say I was sorry the police weren't there, or the transport wasn't there, or the bendy buses didn't work.
"I don't want to be an apologist. What I want to do is create a social movement that will lead people of all political classes, all political persuasions to help us dismantle this poverty," he said.
This was currently entitled The Social Movement, he said, and would be launched "probably some time in February".
"We have to be dispassionate. We have to look at this problem as if we were looking through a microscope at it," Mr Bird said.
"The government is surrounded by practitioners and none of them have any objectivity. In a sense, it's in their interest to be people backing their particular programmes or their particular charities.
"We have to take this shambolic way of social intervention and say where are the problems and what causes them."
Mr Bird launched The Big Issue in 1991, enabling homeless people to make money by selling the news and current affairs publication on the streets.
The full interview with John Bird will be broadcast on Straight Talk on BBC News 24 at 2230 BST on Saturday and Sunday.