Former civil rights leader, Mr Éamonn McCann, is standing in next month's Northern Ireland Assembly election in Derry. He said there had to be a "radical opposition" in Stormont.
He is running in the Foyle constituency where candidates include: SDLP leader Mr Mark Durkan and Sinn Féin chairman, Mr Mitchel McLaughlin.
Mr McCann (60) is standing for the Socialist Environmental Alliance, a left-wing coalition. The SEA is fielding several candidates. Mr McCann said it was challenging "orange-green" politics. He is an outspoken critic of the Belfast Agreement and the institutions set up under it which, he claims, "institutionalise sectarianism".
"If you want things shaken up, the only way to vote is SEA," he said last night. "A vote for any of the others is a vote for more of the same. We are appealing for votes from people of all religions and none. We are small, but intend a big finish."
He said the North was a place of huge inequality. "The top quarter of wage earners have 56 per cent of disposable income, the bottom quarter 6 per cent."
Mr McCann contested the 1970 Westminster election but has not entered the electoral arena since. A journalist, he has long campaigned against the British State for killing 13 civilians on Bloody Sunday.