The annual CST report, released today, shows that over the last 12 months 924 antisemitic incidents were reported.

This is up 55 per cent from the previous high of 598 in 2006, and 69 per cent more than last year's total of 546.

CST spokesman Mark Gardner said: "These record figures show that antisemitism is an increasingly significant problem for British Jews.

"The trend must be reversed and we call upon decent people to speak out against antisemitism in all its forms."

As reported in the Jewish Telegraph last July, the CST had seen more incidents in the first six months of the year than in any entire previous year. There were 628 incidents recorded between January and June.

But even discounting the surge at the start of the year due to the war in Gaza, there were 296 incidents reported between July and December, which is still the same levels as the previous highs of 2006.

Prime Minister Gordon Brown said: "The increase in antisemitic incidents in the early part of last year is deeply troubling.

"I want to be unequivocal - I am a proud friend of Israel and welcome a robust debate about how we ensure both a secure Israel and a viable Palestinian state existing side by side.

"The debate is welcome, but no strength of feeling can ever justify violent extremism or attacks.

"We will stand firm against all who would use anti-Israeli feeling as an excuse or disguise for antisemitism and attacks on the Jewish community."

The percentage of antisemitic attacks that included "extreme violence and assault" was higher in Manchester than anywhere else in the country, with 23 per cent of incidents falling under that category, as opposed to just 10 per cent in London and an average of 13 per cent across the country.

There was a total of 124 violent assaults in 2009 - 41 per cent more than in 2008.

Individual Jews were more likely to be attacked in public in Manchester than in London, with such incidents equating to 70 per cent of all attacks in Manchester and just 37 per cent in London.

Of these, 61 per cent in Manchester involved verbal abuse, as against 41 per cent in London. Chairman of the All-Party Group Against Antisemitism John Mann said: "This report makes disturbing reading.

"While incident figures continue to climb, we must be doing all we can to ensure such hatred is met with our resolute determination to stop it."

And these sentiments were echoed by Denis MacShane, chairman of the European Institute for the Study of Contemporary Antisemitism.

He said: "This sudden rise in antisemitic incidents should be a warning sign that hate against Jews is on the march.

"But when the antisemitic BNP win seats as MEPs, when university campuses host preachers of anti-Jewish hate, or when a British ambassador says Jews should not serve on public inquiries, why should we be surprised?

"The open hate of Israel fanned by jihadi Islamist ideologues is creating an unacceptable climate of fear for Jews.

"Politicians need to take the lead and say loudly and clearly that British Jews should not have to face intimidation and threats."

The reason suggested for the startling figures was the controversy surrounding the conflict between Israel and Hamas in Gaza from December 27, 2008, to January 17, 2009.

Politically motivated attacks were also up significantly, from 172 in 2008 to 442 in 2009 and there were 605 incidents of abusive behaviour, which represents a rise of 91 per cent from the 317 incidents recorded in 2008.

Incidents of damage and desecration to Jewish property rose from 76 in 2008 to 89 in 2009.

And there were 184 incidents involving Jewish community organisations or communal leaders as targets - an increase of 130 per cent from 2008.

Liberal Democrat home affairs spokesman Chris Huhne said: "This steep rise in antisemitic crime is shocking and shameful.

"We must do everything we can to prevent foreign conflicts from spilling over onto British streets and campuses.

"The police must work with all communities to stamp out antisemitism and hate crime and to promote cohesion and tolerance."

Conservative Shadow Secretary of State for Children, Schools and Families Michael Gove said: "Britain's Jewish citizens face a real and growing danger.

"Everyone in public life - politicians, media figures, academics and community leaders - has to recognise that this growth in antisemitism is a stain on our society.

"History tells us that whenever Jewish individuals feel less safe, society as a whole is becoming less free.

"We must learn the lessons of the past and recognise that prejudice against the Jewish people leads to a growth in hatred and intolerance overall.

"Therefore we have to be tough on both antisemitism and the causes of antisemitism."