Luciana Berger has become one of seven MPs to quit the Labour Party.
Berger faced two no-confidence motions from the local branch of her Wavertree constituency earlier this month before both votes were later withdrawn.
Deputy leader Tom Watson urged Labour’s general secretary to suspend the Liverpool chapter over his belief that the politician faced ‘bullying’.
Ms Berger, who has represented Wavertree since 2010, has faced anti-Semitic abuse from within the party and criticised leader Jeremy Corbyn’s stance on it.
She said: “I have become embarrassed and ashamed to remain in the Labour Party.
“I have not changed, the core values of equality for all, opportunities for all, anti-racism against all and social justice.
“The values which I hold really dear and which led me to join the Labour Party as a student 20 years ago remain who I am.
“And yet these values have been consistently and constantly devalued, undermined, violated and attacked as the Labour Party today refuses to put my constituents and our country before party interest.”
She joined Chuka Umunna, Angela Smith, Chris Leslie, Mike Gapes, Gavin Shuker and Anne Coffey in becoming an independent MP.
However the shadow chancellor John McDonnell has urged all seven to resign and contest by-elections in their respective constituencies.
He said: “All of these MPs stood on our manifesto in 2017 – Jeremy Corbyn’s manifesto. They all increased their majorities.
“Now they’re on a different platform so the honourable thing, the usual thing for them to do now, is for them to stand down and fight by-elections back in their constituencies.”