A key source for employees to tackle problems arising from issues including prejudice in the workplace has announced its closure. The National Bullying Helpline confirmed it had shut following the resignation of leader Christine Pratt.

The charity – founded by Pratt and her husband in 2003 – said that the number of calls to its helpline had trebled in 2010, and the “increased workload and trying to secure funding for the charity had taken its toll on the CEO’s health over the last year.”

The helpline service has been stopped with immediate effect but the website will remain in place, the spokesman added. Mrs Pratt, clashed with Downing Street last February when it was alleged Mr Brown, then prime minister, had verbally abused several members of his staff.

She claimed ‘three or four’ calls had been received from people in the prime minister’s office, but later claimed she was not accusing Mr Brown directly.

Number 10 denied the “malicious allegations” and all four patrons of the helpline – including Professor Cary Cooper and Conservative politician Ann Widdecombe – resigned, citing Pratt’s breach of caller confidentiality.

A spokesman said: ‘This last year, calls to our helpline have trebled and we have had to take on additional volunteers and resources to meet demand.

‘Without doubt, this demonstrates that a free anti-bullying helpline is a much needed and much valued life-line for the general public – adults and children alike

According to the National bullying helpline on average 1 in 4 people allege they are being bullied at work and 1 in 8 people are affected by bullying at work.

” The National Bullyingh Helpline’s website states: “We believe our Charity was unique. We believe there is no other UK bullying helpline today, quite like The National Bullying Helpline, providing assistance to both adults and children who are affected by anti social behaviour in the community, the home, the workplace and/or the playground… Undoubtedly, the closure of our Charity will be a great loss to the public”.