The Liberal Democrat leader, Nick Clegg, has spoken out against government mental health policy, claiming that services extended suffer from lack of resources and fail to meet patients' needs.

Mr Clegg claimed that Britain is becoming a “true Prozac nation,” reliant on anti-depressants because of the Government’s “shameful neglect” of mental health services.

The comments come in light of a new report on clinical trials, which has claimed that the most commonly prescribed anti-depressants were no more effective than a placebo for patients with mild depression.

Last year more than 30 million prescriptions were signed for Prozac throughout the UK, with 3.6 million of these being issued in Scotland alone.

It is estimated that 9 per cent of Scots aged 15 or over take anti-depressants daily. This equates to almost 370,000 people and £43.7 million worth of prescriptions.

As a result, Scottish Health authorities spend 40% more per head of population than the rest of the UK on anti-depressants.

Nick Clegg has committed his party to a guarantee of NHS treatment for mental health issues within 13 weeks.

Scots currently have to wait more than a year for Cognitive Behavioural Therapy (CBT) which is a method of treating depression without resorting to medication.

The Scottish Government has urged doctors to use alternative methods for treating depression, pledging to halt the rise in prescriptions by 2009.

Alison Cobb, representative of Mind, the mental health charity, said the study provides a "serious challenge to the predominance of drugs in treating depression."

She said: "Anti-depressants do help many people but by no means all. Nine out of ten GPs say they've been forced to dish out drugs because they don't have proper access to 'talking treatments' such as CBT.”

However, Dr Tim Kendall, Deputy Director of the Royal College of Psychiatrists Research Unit, has argued that "those who are taking them and enjoying benefit, should continue to do so."