Lord Mitchell has been a passionate advocate, a tireless activist, and an inspirational role model for my Party and the labour movement.

Given the appalling antisemitism that is plaguing the Labour Party, his decision this week to resign from the Labour Party is one that I can understand. But it is not one that I can ever agree with. The Labour Party has been the driving force of progress for our country and our community for 116 years, and we owe it to the people it was founded to serve to stand and fight at this moment of crisis.

The antisemitic bullying and intimidation that has infected our party in recent months is heart breaking and infuriating. I know better than most people just what damage this cancer is doing to a party I have been proud to be a member of since I was a teenager.

But this is my party, however much the antisemites might wish it wasn’t. This is the party that my parents and grandparents have supported through thick and thin, because they understood that the Labour Party is the best vehicle for social justice our country has ever known.

And it is the party of Shinwell, and Mikardo, and Abse – proud Jews and proud socialists who have left an indelible mark on our nation’s history.

We cannot allow our party and its proud history to be hijacked and degraded by a small band of ideological zealots. We cannot walk away and allow the forces of bigotry to fill the vacuum. We cannot, and I will not, let these momzers win.

So as you watch the current crisis in our party, turn your mind to the immortal words of the labour movement: Don’t mourn, organise.

Now is not the time to walk away. It is the time to stand and fight for what we believe in. Our party, and our country, demands nothing less.