He also previously attacked the IHRA definition of antisemitism and, once Labour had adopted it, tweeted that "Israel is a racist endevour [sic]" to mock it.
He even attacked Momentum, the pro-Corbyn campaign group, for acknowledging Labour's antisemitism issue, saying it should rename itself "Momentum Friends of Israel".
He wrote that Joan Ryan, the chair of Labour Friends of Israel who quit the party last month, saying she had "fabricated antisemitism".
This week, it was revealed on Twitter that Mr Winstanley was a member of the Brent North Constituency Labour Party and had signed an open letter urging the party's governing body not to adopt the IHRA antisemitism definition.
A party spokesman said Labour did not comment on individual cases but said on Thursday evening: "The Labour Party takes all complaints of antisemitism extremely seriously and we are committed to challenging and campaigning against it in all its forms.
"All complaints about antisemitism are fully investigated in line with our rules and procedures and any appropriate disciplinary action is taken."
After a JC journalist revealed Mr Winstanley's suspension on Twitter, he said this "would, if true, be confidential" and it "indicates attempts to politicise and compromise Labour's disciplinary process".
