Jewish institutions will undergo a cut in funding for security measures after the US Department of Homeland Security slashed a counter-terror grant programme by nearly 50 per cent.

The department's budget for the Nonprofit Security Grant Programme (NSGP) has been reduced from $19 million last year to $10 million this year.

Yehudit Barsky, director of the division on Middle East and International Terrorism at the American Jewish Committee, said that, as a result, there would be fewer Jewish organisations that could apply for grants this year.

Paul Goldenberg, National Director of the Secure Community Network, said the cuts were "absolutely a concern". He added that "the community has to become much more vigilant and depend more on the human factor - on training, testing and developing security plans, volunteerism, awareness-raising, vigilance."

On the threat level faced by Jewish bodies in the US, Mr Goldenberg said: "Synagogues remain very much in the crosshairs. Those who want to attack America are not distinguishing between Israeli and Jewish institutions.

"It's not our imagination that there have been many cases of people plotting to attack Jewish institutions in this country."

An investigation by Forward magazine found that, between 2007 and 2010, 73.7 per cent of the grants went to Jewish organisations. About 45 per cent of these were allocated to Orthodox groups.

The NSGP is designed to assist non-profit organisations that are at high risk of terrorist attacks with physical security enhancement, particularly in metropolitan areas.

The Forward report claimed that the disproportionate distribution of funds to Jewish groups was a result of their political power and that the NSGP has become a "Jewish earmark programme".

Ms Barsky called this a "very serious charge" which "accuses the DHS of having some type of special consideration only for the Jewish community".

Ms Barsky said that there was a great deal of competition for the grants, which cover things like surveillance cameras and shatterproof windows.

"You have to show that institutions such as yours have previously been under threat. Unfortunately, many Jewish institutions [in the US] have been targets."

"In the past 2.5 years," Ms Barsky said, "a significant number of homegrown terrorists in the United States have included Jewish institutions on their target lists, and that has been taken notice of by the DHS and law enforcement agencies."