The man who heckled Jeremy Corbyn at last year’s Labour Friends of Israel event has mounted a legal challenge to keep him off the ballot following a leadership challenge from MPs Angela Eagle and Owen Smith.

Michael Foster, whose family is reported to have donated £400,000 to Labour’s general election campaign, wants the Labour leader to have to secure the support of 51 MPs, the minimum needed for any challenger.

This week Labour’s National Executive Committee voted by 18 votes to 14 that, as incumbent, Corbyn did not need to garner enough votes to meet the threshold.

Speaking on Radio 4’s Today programme, Foster – a Jewish donor and former parliamentary candidate – said it was a question of “interpretation of the rules, whether they give the incumbent the right to stand without the relevant nominations”.

Several lawyers, including Michael Mansfield QC, have concluded that Corbyn should be automatically on the ballot, saying: “The rules are unambiguous.”

Foster, who said he did not vote for Corbyn, denied that “this is about politics” saying: “The advice that was taken was not given the expert consideration that it would receive from a High Court judge, and everyone in the [NEC] room had a different political agenda.” If the case is heard, Foster said it would be heard “within days”.

Last year, shortly after Corbyn won an overwhelming mandate from Labour party members, Foster stood at the back of a Labour Party conference fringe meeting in Brighton shouting: “Say the word ‘Israel,’ say the word ‘Israel,’” after Corbyn addressed LFI supporters. Foster later also criticised Corbyn for not saying the words ‘Jew’ or ‘Jewish.’