Under-fire UK Labour general secretary Jennie Formby twice told a meeting of MPs and peers that it was impossible to fully “eradicate” antisemitism from her party.

Attempting to convince Monday’s meeting of the Parliamentary Labour Party (PLP) that under Jeremy Corbyn’s leadership there was a concerted effort to tackle Jew-hate, she said: “I don’t think anyone can ever say that we can eradicate antisemitism completely and stop every single person from making … every single day someone else could join the party tomorrow and do something.

“What I want to make sure is that we have processes and procedures that deal with people who do (engage in) antisemitism within our party. “And I think that’s very important.”

She then added: “Anyone who thinks that they can completely eradicate something – then they are being dishonest.”

After Formby made her controversial remarks – in front of a packed meeting that was observed in silence by shadow Home Secretary Diane Abbott, shadow chancellor John McDonnell and party chairman Ian Lavery – angry backbench MPs openly voiced their anger.

Resentment increased after Formby confirmed she would not be able to provide a full report answering all eleven questions relating to Labour’s disciplinary processes over antisemitism.

The successful motion, which had been proposed by Newcastle North MP Catherine McKinnell, demanded answers from the leadership in one week. It was unanimously passed by the PLP at the packed meeting in Westminster.

Dame Margaret Hodge protested to John Cryer, who chaired the meeting: “Jenny has just told us she is not going to comply with the terms of the resolution that has been passed unanimously by this PLP. In those circumstances what are you going to do and what are other members the NEC going to do protect our rights to have that information?

“I’ve never heard such a vacuous argument, if one really does want to kill that terrible cancer of people feeling we’ve become institutionally antisemitic.

“The most important thing you can do is provide the information and data.” Ilford North MP Wes Streeting also complained about the lack of “transparency” from the leadership over the backlog of outstanding antisemitism cases.

He said: “Frankly in terms of the data we demand off government when it comes to the types of cases, the numbers of cases, and how they are dealt with – we expect transparency from government – is it not unreasonable to expect it from the party?”