The pioneer of Portsmouth City Council's Labor bunch hosts surrendered from the gathering taking after Jeremy Corbyn's re-race.
John Ferrett hosted been an individual from the gathering for a long time and remained when all is said in done decisions in 2010 and 2015.
He said the gathering under Mr Corbyn had turned into a "challenge development that has no enthusiasm for winning force".
Mr Corbyn requested for solidarity in the wake of being re-chosen as Labor pioneer, vanquishing challenger Owen Smith.
Work controlled Portsmouth City Council in the late 1990s, however Mr Ferrett had driven a gathering which had tumbled to only three by the decisions of 2014.
Mr Ferrett said he settled on the choice to leave "with a substantial heart".
"Work generally has had genuinely solid base in Portsmouth however the most recent five years, even under Ed Miliband, it's been ridiculously difficult to set up Labor as a tenable gathering and now under Jeremy Corbyn we'd discover it verging on difficult to win in spots like Portsmouth.
Mr Ferrett approached individuals from the Parliamentary Labor Party to make another political gathering as a "contemplated social just option" to the Conservative government.
He said he would proceed as an autonomous councilor and counsel occupants in his Paulsgrove Ward.
Mr Corbyn secured 61.8% of the vote to easily vanquish his challenger Owen Smith in the administration decision.
Among those calling for gathering solidarity, Shadow Foreign Secretary Emily Thornberry said it was the ideal opportunity for rivals of Mr Corbyn to fall in line, they expected to work for "more prominent's benefit" by giving a solid resistance.