"They’ve done this by terrifying activists, coordinating with anti-Corbyn journalists and MPs, and using faith organisations, many of them charities, to promote the antisemitism narrative.
“First they said ‘anti-Zionism is antisemitism’, then they said ‘anti-capitalism is antisemitism’. In this election, they’ve sought to prevent dozens of anti-imperialist socialists from standing for Labour.”
Mr Williamson attacked "apologists for apartheid", saying they waged a "concerted smear campaign" against the party.
He said Labour had "internalised the antisemitism narrative promoted by the far-right Israeli Government... but we'll not allow racists to dictate to us on the left what anti-racisism means".
He said he would use money raised by crowdfunding for his own legal case against his old party to create a "Left Legal Fighting Fund" to defend others who Mr Williamson said were "maliciously smeared and harassed by the same allegations".
Mr Williamson resigned from Labour in order to stand as an independent. He won just 635 votes in Thursday's election.
His seat was taken by the Conservatives, who now have a 2,015-majority there.
