David Cameron was accused of insensitivity today after making a joke about suicide in his keynote address to the Conservative Party conference in Birmingham.

Mr Cameron departed from his planned script after joking about the prospect of Gordon Brown remaining in power forever, adding: "I won't go on - there are people in balconies up there”.

The quip prompted a loud laugh in the hall but fell flat with a group dedicated to helping those affected by suicide.

Angela Samata, Trustee of Survivors of Bereavement by Suicide, said that Mr Cameron's comment was "very insensitive" and could be “extraordinarily upsetting for people in our situation: people who have been bereaved by people who had perhaps jumped to their deaths".

She said that those bereaved by suicide are "very, very sensitive to comments like that".

"We come up against this kind of thing time and again, it's quite a big issue for us,” Ms Samata said. “For some people it's a well-used turn of phrase, but for someone who could be the next Prime Minister you would expect a certain level of sensitivity."

Mr Cameron's joke was especially ill-timed given news reports about 17-year-old Shaun Dykes, who threw himself from the top of a city centre car park in Derby at the weekend.

Police who tried to dissuade the teenager from taking his own life complained that a crowd of up to 300 people had gathered in the street below to taunt him. One had even shouted: "How far can you bounce?"

Mr Cameron's faux pas also came on the day that one of his frontbenchers, the local government spokesman Eric Pickles, was forced to apologise for making a joke about John Prescott's bulimia.

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