The Chief Rabbi has told US Secretary of State Mike Pompeo that the "walls of prejudice are closing in" on Jews.
At a meeting with faith leaders and Foreign Secretary Jeremy Hunt at Lambeth Palace on Wednesday, Chief Rabbi Ephraim Mirvis said the threat was coming from both ends of of the political spectrum.
He told the room: "As Jews, today we feel particularly vulnerable. The walls of prejudice are closing in on us from both the far left and the far right.
“Here in the UK, we have particularly struggled with anti-Jewish racism on the left in recent years and we are witnessing a disturbing increase in far right extremism right around the world.
“It is tragic that when we enter into our synagogues and schools we do so via security barriers, but it is a necessary deterrent.
"We are grateful to our government in the UK for the funding it makes available to protect people at prayer and the rest of the world can learn a lot from the example that it has set."